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EDITORIAL _____________
201
William E. Boyajian
Russell Shor
Chronicles the key developments and events that have radically transformed the global diamond industry in recent years.
234
pg. 222
pg. 238
Lab Notes
Unusual synthetic alexandrite with needles and crystals Dyed rough diamond
Strongly colored natural type IIb blue diamonds Large natural freshwater pearl
from Texas Natural pearl, with a round core, that appears cultured Large
baroque golden South Sea cultured pearls Synthetic turquoise necklace
Yttrium zirconium oxide
264
279
280
281
Book Reviews
285
Gemological Abstracts
pg. 260
pg. 269
EDITORIAL
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During the past 15 years, political and economic forces have converged to radically transform the
structure of the diamond industry worldwide. This article examines how upheavals in the former
Soviet Union and several African nationsas well as the arrival of new sources such as Australia
and Canadaled to the restructuring of the rough diamond market. This in turn created new
competitive pressure at the wholesale and retail levels, including the movement to establish new
diamond cuts and diamonds as branded items. At the same time, technological advances have
enabled the faster, more efficient manufacturing of rough diamonds, created new treatments, and
fostered the introduction of economically viable gem-quality synthetics. While demand for diamond jewelry remains strong in the U.S., which accounts for nearly 50% of world consumption,
new markets such as India and China are likely to spearhead continued growth. In addition, new
social and governmental initiatives have affected how the entire industry conducts business.
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of several Asian economies in the late 1990s delivered a devastating blow to some diamond operations.
In addition, diamond sources in Australia and
Canada were developed by mining companies that
challenged De Beerss traditional single-channel sales
market. A diamond manufacturer, Lev Leviev, also
became a major rival to De Beers by securing lucrative diamond sources in Angola, Namibia, and
Russia. De Beers recast its own operations at the turn
of the millennium and tried, along with industry
bankers, to shift the industry from a supply-driven to
a demand-driven mentality, pushing its sightholders
to greater vertical integration and investment in sales
and marketing programs. Meanwhile, diamond-producing nations began asserting greater control over
their resources, including demands that a share of
their bounty be processed locally. This has profound
implications for diamond manufacturers in all parts
of the world, as well as for distributors in the middle
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million carats (table 1). The majority of world production was concentrated in southern Africa, with other
sources including Australia and the Soviet Union
(Levinson et al., 1992). Through its single-channel
marketing approach, formally adopted in 1935
(Diamonds, 1935), De Beers still managed the distribution of the vast majority of rough diamonds
entering the world market. Yet within 10 years,
changes in De Beerss relationships with Russian and
Australian producers, the development of mines in
Canada, and political events in Africa would dramatically reduce De Beerss share of the market and greatly alter the entire dynamic of the diamond industry
(Even-Zohar, 2002). The map of world diamond production and major cutting centers that Boyajian published in 1988 (p. 149) has undergone some significant changes (figure 2).
Some of the most radical changes came in the production and distribution of rough diamonds. In 1991,
worldwide production totaled approximately 106
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203
Africa, South America, and elsewhere; informal alluvial mining in West Africa; and market windowsa percentage of rough diamonds the CSO
permitted its contracted producers to sell on the
open market to gauge prices.
The CSO mixed rough diamonds from all sources
and sorted them by quality, shape, and weight criteria (figure 4). Ten times yearly, it marketed rough to
a specific roster of clients at sights. In times of
slack demand or overproduction, the CSO would act
as a market buffer by stockpiling diamonds or reducing their purchases from certain producers (effectively forcing them to stock at the mine sites).
Yet several forces were developing that would significantly affect the CSOs ability to maintain a
majority share of the rough diamond market, hold
stocks of rough to regulate price fluctuations, and
fully control rough diamonds it obtained from its
TABLE 1. World rough diamond production by country, 19912003 (in thousands of carats).a
Country
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
1,100
18,078
11,160
8,934
1,520
9,000
180
4,600
2,737
130
18,844
10,310
2,006
1,120
8,000
90
4,600
2,612
270
19,485
10,550
4,000
1,312
8,500
155
4,340
2,746
2,600
18,300
11,500
4,000
60
1,382
10,500
113
5,070
2,117
2,250
18,897
12,400
3,600
60
1,402
10,500
162
4,400
1,853
1,110
18,100
15,100
3,000
80
1,345
10,500
300
4,500
2,568
2,400
18,400
14,800
300
3,300
150
1,394
11,500
200
4,300
2,235
3,360
13,403
17,200
2,429
4,120
120
1,630
11,500
7
4,000
2,883
3,914
11,956
18,500
2,534
3,500
100
1,450
11,600
58
4,320
3,300
4,653
11,779
19,800
3,716
3,640
100
1,487
11,600
167
4,470
3,122
4,520
15,142
21,300
4,984
4,400
48
1,350
11,500
147
4,350
2,888
4,770
14,900
22,800
11,200
5,400
36
1,650
12,000
214
5,070
2,910
51,000
57,300
47,700
51,400
55,700
55,500
56,600
58,900
60,600
61,200
64,500
70,600
80,900
Industrial
Angola
62
Australia
17,978
Botswana
4,950
Zaire/D. R. Congo 14,814
Liberia
Namibia
20
USSR/Russiac
10,000
Sierra Leone
83
South Africa
4,600
Other
2,300
80
22,095
4,790
4,567
30
9,000
116
5,600
2,206
15
23,032
4,420
13,620
20
8,000
68
5,700
2,488
30
23,815
5,000
13,000
8,500
100
5,343
2,561
300
22,400
5,300
13,000
90
10,500
101
5,880
2,505
250
23,096
5,000
17,000
90
10,500
108
5,550
2,663
124
22,100
5,000
17,600
120
71
10,500
100
5,540
2,201
364
22,500
5,000
18,900
150
73
11,500
50
6,460
2,326
373
16,381
5,730
16,000
80
11,500
2
6,010
1,553
435
14,612
6,160
14,200
70
106
11,600
19
6,470
1,646
517
14,397
6,600
14,560
70
11,600
56
6,700
1,621
502
18,500
7,100
17,456
32
11,500
205
6,530
1,638
530
18,200
7,600
21,600
24
12,000
296
7,600
1,632
48,500
57,400
58,300
60,100
64,300
63,400
67,300
57,600
55,300
56,100
63,500
69,500
Namibia
1,170
USSR/Russiac
10,000
Sierra Leone
160
South Africa
3,800
Other
2,433
Total
Total
Grand total
54,800
106,000 106,000 105,000 110,000 116,000 120,000 120,000 126,000 118,000 117,000 121,000 134,000 150,000
a Totals may not match individual values because of rounding. A " in a block indicates no production or negligible production reported. Sources: Balazik
(1995); Olson (1999, 2003). Note that other sources may use different numbers because much of the information is based on estimates.
b Total production. Separate figures for industrial diamonds not available.
c
All Russia/USSR data before 2003 are based on estimates, with output believed to be 50% gem and 50% industrial.
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Figure 2. Diamond production in the 1980s was largely concentrated in southern Africa, with a few major mines
in Australia and the USSR. There are now major producing countries (dark green) on every continent except South
America and Antarctica; these eight countries accounted for over 95% of world production by volume in 2003.
Approximately a dozen other countries (medium green) produce commercially significant amounts, though far
less than the major producing nations. The major cutting and trading centers are indicated with a red diamond.
Modified from Boyajian (1988).
investors believed such a stockpile was a growing liability, and the price of the companys stock ultimately fell because of it (De Beers Consolidated Mines,
1997). In addition, because De Beers executives had
made the high-quality goods flowing from Angola
such a priority, they were disinclined to protect the
market for small diamonds. This concerned Argyle
executives and contributed to their decision not to
renew their marketing agreement with the CSO
(Shor, 1996c).
Third, the discovery of diamonds in Canada
introduced a large rival mining corporation, BHP, to
the diamond market, thus creating another
formidable distribution channel outside the CSO.
Finally, after 1999 the CSO (renamed the
Diamond Trading Company, or DTC, in 2000)
stopped buying goods on the outside market in
order to reduce its large diamond stockpile, which
had grown to $4.8 billion (De Beers Consolidated
Mines, 2000). In addition, it did not want to handle
so-called conflict diamonds from embattled nations
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The end of the Soviet regime led to a new diamond industry structure that divided power and
profits between the central government in Moscow
and the local authority in Sakha, the semiautonomous republic that produces 98% of Russias
diamonds. The mining and marketing of diamonds
from the Russian Federation was placed under a
joint-stock (cooperative venture) agency known
as Almazziirossi-Sakha (now shortened to Alrosa),
Russian for Diamonds of Russia and Sakha.
Ownership of Alrosa is divided as follows: Sakha
Republic, 40.5%; the central Russian government,
32.5%; other government agencies, 27%.
Alrosa took 80% of Russias yearly rough production of approximately $1.2 billion; the Republic
of Sakha took the other 20%. Those shares continue today. With the dissolution of the USSR, Alrosa
continued to honor a clause in the 1990 agreement
with De Beers that required it to sell 75% of its
rough production to the CSO. The remaining 25%
would go to Russian polishing operations or be sold
through Alrosas office in Moscow. At the same
time, Sakha signed its own contract with the CSO
to sell all of its production, apart from a provision
for unspecified allocations to local polishing operations. This would prove problematic.
The 1990 agreement contained several critical
loopholes: It did not include goods from Russias
estimated $3 billion stockpile, which were administered by a different agency controlled by the central
government (Komdragmet, later called Gokhran); it
did not define or limit the scope of domestic polishing operations (most of which were in fact newly
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created joint ventures with Antwerp or Israeli manufacturers); and it did not include sales of technical (industrial) diamonds (Shor, 1993).
By 1992, diamonds were pouring through these
loopholes, depressing pricesparticularly of small
goods. Worse for De Beers, some of the 37 cutting
operations did little more than polish a window
onto a rough diamond and export it as polished
(Even-Zohar, 2002). An estimated $5 billion worth
of rough diamonds thus leaked into the market during the mid-1990s (Pearson, 1998). The influx of so
many diamonds caused serious instability in the
diamond market.
In October 1997, after two years of difficult
negotiations, the Russian government and the
CSO finally signed a new contract that would last
until the end of 1998. It was based on a complex
formula stipulating that Russia, through Alrosa,
sell the CSO a minimum of $1.2 billion of rough
diamonds, drawn from both new mine production
and the stockpile. The agreement closed two crucial loopholes: It banned the export of partially
manufactured diamonds, and it tightened the standards for technical diamonds so they were much
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207
with RTZ in 1995 and took the name Rio Tinto two
years later), signed a deal to sell the CSO 75% of their
yearly output. Approximately 40% of these diamonds could be fashioned into polished goods
albeit, for the most part, of very low qualityby
Indias low-wage manufacturing force (the effects on
India are detailed below). At first, these vast quantities of smaller, lower-quality material were easily
absorbed by fast-growing U.S. mass merchandisers,
who found a market niche for affordable diamond
jewelry. However, Argyle production neared full
capacity by 1991 as the U.S. economy fell into a
recession, swelling inventories of small diamonds in
the cutting centers. Then the large, unregulated flow
of small diamonds from Russia in the early and mid1990s (discussed above) depressed prices and bloated
inventories, prompting De Beers to impose a 25%
reduction in its purchases of rough from each producer (Shor, 1996b). The move generated unease among
Argyle executives, who believed De Beers had failed
to support the market for small diamonds at the
same time that it had propped up the market for larger diamonds when supplies of such goods from
Angola threatened to overwhelm the pipeline.
As a result, Argyle declined to renew its sales
contract with De Beers in 1996. This decision sent
fears of a price war between the CSO and Argyle circulating through Indias diamond industry.
Argyle also broke precedent with other diamond
producers by launching its own marketing campaign, beginning in 1990 (Shor, 1991). The company
developed a sales organization and marketing initiatives aimed at driving demand for smaller diamonds
and the millions of carats of brown goods the mine
produced, which it christened champagne and
cognac (Shor, 1991; figure 5). Argyle then focused
on promoting finished jewelry made by major purchasers of its diamonds, hiring jewelry manufacturing technicians to assist these firms in developing
products and services compatible with American
retailers requirements (Shor, 1994) and engaging a
marketing organization (Market Vision International [MVI]) to facilitate access to U.S. retailers
at major trade shows. By 2004, Indias diamond jewelry exports had topped $2 billion, nearly two-thirds
of which were destined for U.S. retailers (Weldon,
2004a).
While achieving success at building demand for
its clients products, Argyles owners were faced with
a critical decision as the millennium neared: The projected life of the mines open-pit operation (figure
6) was coming to an end. Production had nearly
208
Figure 5. During the 1990s, a series of marketing initiatives by the owners of the Argyle mine in Australia
helped make fine brown diamonds such as these
(0.351.32 ct) an important segment of the colored
diamond market. Photo Robert Weldon.
halved to 26.2 Mct by 2001, after Rio Tinto conducted a redevelopment project to extend its life. This
reduction in Argyles output created a large overcapacity of diamond manufacturing in India, which
touched off a heated competition for rough supplies
to keep the many operations going (Gross, 2003). By
mid-2005, the projected cost of converting Argyle
into an underground mine was estimated at A$1.05
billion (US$800 million). Rio Tinto has pressured the
Western Australian government for aid and concessions on the 22.5% it pays in royalties to keep the
mine operating past 2008 (Tanna, 2004a; Argyle
expansion, 2005). Closure of Argyle would exacerbate the overcapacity of Indias diamond-manufacturing operations, particularly in Ahmadabad, where
vast quantities of those stones are polished.
Canada. The 1991 discovery of diamond-bearing
kimberlite at Lac de Gras in Canadas Northwest
Territories was the first significant diamond find in
North America. Ultimately, the Canadian mines
would become the first major operations in recent
times to sell the majority of their production outside the CSO from the beginning.
By the time the mine finally opened in October
1998, BHP Minerals (now BHP Billiton) had established a marketing subsidiary, BHP Diamonds,
which opened a sales office in Antwerp, run in cooperation with rough diamond dealer IDH Diamonds
(Shor, 1999). In the first two years of operation,
Ekatis main pipe, Panda, yielded a total of 2.7 Mct,
about 2% of world diamond production by weight
and 5% by value. By 2003, annual production had
increased to 4 Mct, worth just over $600 million
(Rio Tinto Diamonds, 2003).
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catalyst that helped Leviev become the first significant competitor to De Beers in the control and distribution of rough diamonds.
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which seek to integrate the countrys majority population into its large corporate community (Mbeki,
2004; Mlambo-Ngcuka, 2004).
The legislation would put into practice principles espoused in the countrys new Mining Charter,
which asserts that all mineral resources are the
property of the people of the country, with the state
holding custodial rights. The laws would cede broad
discretionary powers to the minister of minerals
and energy in granting and administering prospecting and mining operations, require mining companies to set aside a percentage of rough diamonds for
local manufacturing, and allow domestic cutters
first refusal rights on rough diamonds.
Thenminister of minerals and energy (now
deputy president) Phumzile Mlambo-Ngcuka (figure 9) told attendees at the 2004 Antwerp
Diamond Conference that local cutters should be
empowered to decide what they can and cannot
cut rather than producers who are keen to sell outside [South Africa] (Mlambo-Ngcuka, 2004).
However, experiences in Canadas Northwest
Territories (NWT) demonstrated the difficulties of
such operations. In 2005, Sirius Diamonds, a cutting facility established with aid from the provincial NWT government, went bankrupt. De Beers
chairman Nicky Oppenheimer, addressing a gathering of African mining ministers on February 8,
2005, noted that diamond manufacturing in highwage countries (e.g., South Africa) can run
$40$50 per carat, yet must compete with large,
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212
Namibia. This country has been a producer of highvalue marine diamonds for nearly 100 years.
Production averaged about $275 per carat in 2000
(Even-Zohar, 2002). After Namibia achieved independence in 1990, newly elected president Sam
Nujoma negotiated with De Beers, which owned all
of the major diamond-producing concessions, to
transform mining operations into a 50-50 governmentDe Beers corporation called Namdeb, created
in 1994. Nujoma later encouraged other diamond
producers and manufacturers to invest in the country, with the eventual goal of having 90% of
Namibian-mined diamonds polished locally. As of
mid-2005, five local polishing operations (see, e.g.,
figure 10) had been established, including a 550worker facility opened by Lev Leviev.
At a November 2004 ceremony in Windhoek,
De Beers managing director Gary Ralfe offered to
help the government develop skills and jobs in the
country, which produced 1.65 Mct in 2003 (Tanna,
2004b). In mid-2005, Ralfe opened a branch of
Diamdel, the DTCs rough diamond distribution
subsidiary, in Windhoek to supply local diamondmanufacturing operations (De Beers Group, 2005).
Botswana. De Beers and the Republic of Botswana
have been partners in the worlds largest diamond
reserves since 1967. There are three major diamond
mines in the countryOrapa, Jwaneng (figure 11),
and Letlhakaneand a smaller, newly opened operation, Damtshaa. These are owned jointly by De
Beers and the government of Botswana through a
50-50 venture, Debswana.
The sheer volume of Botswanas production,
30.4 Mct valued at $2.4 billion in 2003 (Debswana,
2003), combined with the fact that diamond revenues account for 3540% of the countrys gross
domestic product, have placed the two entities into
an interdependent relationship. This was formally
sealed in 2001 when Botswana became the first diamond producer to gain an ownership stake in De
Beers. Debswana took a direct 11% share, and an
indirect 4% share when De Beers reorganized as a
private concern that year (discussed in detail below;
De Beers Consolidated Mines, 2001; Even-Zohar,
2002). Botswana president Festus Mogae made it
clear in a November 2002 talk in Antwerp that diamonds have been the key to his countrys rapid
development and ascendance into a middle-class
society, according to World Bank classifications.
Despite their close relationship, De Beers and
the government of Botswana have engaged in hard
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CONFLICT DIAMONDS
While mining companies and governments vied to
develop and control kimberlite deposits, the alluvial fields of western (Sierra Leone), central
(Democratic Republic of Congo [DRC]), and southern (Angola; figure 12) Africa brought to official
and public attention, for the first time, concerns
over the origins of diamonds. Civil wars in these
regions sparked a series of United Nations sanctions on trading diamonds from those countries,
beginning in 1998. These stones became known as
conflict diamonds, which the U.N. officially
defined in 2000 as: Diamonds that originate from
areas controlled by forces or factions opposed to
the legitimate and internationally recognized gov-
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MANUFACTURING TECHNOLOGY
Until the early 1990s, the process of polishing diamonds had changed little from traditional methods developed during the previous century. Most
diamond-cutting procedures were still accomplished by hand (Caspi, 1997). The main exception
was the automated polishing machine for round
brilliants, introduced by Piermatic in the 1970s.
During the late 1980s, however, a confluence of
events and technologies revolutionized the diamond-cutting process, allowing goods to come to
market much more quickly and efficiently. They
also increased yield significantly, by giving manufacturers many more options, and permitted new
shapes to be fashioned economically.
The most important event was the rise of Indian
and other Asian manufacturers in the quality-diamond field, which forced diamond manufacturers
in so-called traditional centers, Israel in particular,
to look at automating their operations to remain
competitive. Indian labor costs ran one-fifth to onesixth those of Israeli workers (Caspi, 1997). In addition, Asian consumersthe Japanese in particularwere very sensitive to the quality of diamond
cut (Shor, 1996e). Moreover, as price competition
among retailers intensified, diamond manufacturers were compelled to derive the maximum yield
from their rough without sacrificing beauty.
Israeli engineers adapted emerging technologies
of lasers, computer imaging, and precision measurement systems to diamond processing. Major
producers such as Argyle and De Beers also made
improvements in automated diamond-processing
equipment, such as polishing and bruting
machines, to increase speed, accuracy, and quality
(Caspi, 1997).
Lasers had been used by diamond manufacturers
since the 1970s to remove dark inclusions, but
those early lasers lacked the precision to be adapted
to the cutting process, resulting in losses of about
8% of the rough (compared to 1% to 2% by conventional sawing). By the 1980s, though, some manufacturers in India adapted lasers for kerfing (cutting
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DIAMOND CUT
The preference for well-made diamonds that Japanese
consumers developed during the late 1980s was
spurred in large part by the introduction of specially
made viewers in retail shops. These viewers displayed a round brilliant diamonds optical symmetry
in the form of a hearts and arrows pattern created
by the reflection of the facets (Miller, 1996; figure 16).
The Japanese example began migrating to the
U.S. during the 1990s, as American consumers
learned more about diamonds, including the fact
that appearance depended as much on cut as on
other quality factors. A spring 1997 survey by JCK
and New York Diamonds noted that 15% of retail
jewelersmainly those concentrated at the upper
end of the marketsaid their clients were willing to
pay a premium for a well-made diamond (Shor,
1997a). Five years earlier, that percentage had been
negligible. Also in 1997, Lazare Kaplan International (LKI), which had long based its market
niche on ideal cuts, reported a 50% increase in
polished diamond sales (Shor, 1997a).
The following year, GIA published the initial
results of its extensive research project on diamond
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CONSUMER DEMAND
Consumer demand for diamonds stagnated through
much of the 1990s, even registering small yearly
declines between 1993 and 1998 (Katz, 2005),
because of growing competition from other luxury
products and economic problems in several key
consumer markets. Demand rose sharply in U.S.
dollar terms after 2001, though some analysts maintain that higher sales figures have stemmed more
from price increases than actual volume.
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While sales in the U.S., the worlds largest diamond-consuming market, remained relatively
steady, the aggressive entry of discount merchandisers into diamond jewelry during the 1980s put pressure on traditional wholesalers because the large
retailers bypassed them to purchase directly from
diamond-cutting centers. These retailers used their
volume buying ability to wrest control of diamond
prices from manufacturers and dealers (Pearson,
1998), thus creating a profit-margin squeeze that has
not abated. The relentless discounting by these
retailers and, later, major retail jewelry chains,
exerted further downward pressure on retail diamond prices. By 2003, the profit squeeze had halved
industry margins to 78%, prompting concern from
leading industry bankers (Gross, 2003). This stagnation of sales in the 1990s contributed to De Beerss
decision to embark on a major recasting of its sales
and distribution procedures.
Boom and Bust in Asia. Extremes in the Asian
markets also played a critical role in pushing De
Beers to recast its traditional role as market buffer.
Sales of diamond jewelry in the U.S. and Japan (the
two biggest markets, consuming nearly two-thirds
of all diamond jewelry) ran nearly even from 1988
until the mid-1990s. However, when economic
stagnation took hold in Japan in the early 1990s,
jewelry sales declined abruptly. As one indication,
79% of Japanese brides received diamond engagement rings in 1995, but only 64% two years later.
By 1998, Japans share of the world market for diamond jewelry had shrunk to approximately 20%
(Ralfe, 1999).
Elsewhere in Asia, economic growth in emerging markets such as Korea, Thailand, the
Philippines, Malaysia, and China took off in the
early 1990s. This caused a dramatic rise in regional
diamond jewelry sales, from negligible in 1980 to
nearly 7% of world volume by 1995. South Korea,
in particular, saw a boom in diamond jewelry consumption, despite various luxury taxes that added
more than 50% to the purchase price (Shor, 1997c).
Sales of diamond jewelry there reached an estimated $1 billion in 1996, fourth in the world, up from
near zero in 1988, when the country first allowed
diamond imports. Sales of diamond jewelry in
Thailand reached the half-billion-dollar mark in
1995, and De Beerss market watchers were closely
monitoring rising diamond sales in the Philippines
and Malaysia. Nevertheless, these markets could
not compensate for the decline in Japanese demand.
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220
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Jennifer Lopez and Whoopie Goldberg and the blingbling (large, costly jewelry worn by celebrities) fad.
Colored diamonds had finally become ingrained in
the consumer consciousness (King, 2003; figure A-1).
One key indicator is that requests for natural-color
colored diamond grading services at GIA increased
68% between 1998 and 2003. This popularity led a
group of prominent manufacturers to form the
Natural Colored Diamond Association in 2004. The
group helped feature natural-color colored diamonds
in various fashion shows and at the 2004 Academy
Awards (NCDia, 2004).
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TREATMENTS
The use of various methods to enhance the color
and/or clarity of colorless to near-colorless diamonds
is one of the most important developments of the
last 15 years. Until the late 1980s, there were virtually no significant treatments for near-colorless diamonds. The 1990s and beyond brought new, highly
controversial diamond treatmentssome of which,
unlike most earlier gem enhancements, presented
considerable identification challenges for gemologists. The filling of fractures in diamonds with a
lead-based glass to improve the apparent clarity had
been introduced in the late 1980s (see, e.g., Koivula
et al., 1989). Because retailers were not accustomed
to checking diamonds for treatment, many of these
filled stones entered the marketplace without disclosure, with tragic results in at least one case (see, e.g.,
Overton, 2004b). Yet fracture filling was, and continues to be, readily identifiable with magnification.
In the 1990s, a significant controversy developed
around an older treatment: laser drilling to remove
dark inclusions. When the Federal Trade Commission adopted its revised Guides for the Jewelry
Industry in 1996, it did not require disclosure of
laser drilling. The Diamond Manufacturers and
Importers Association (DMIA), a New York trade
organization, argued that the process did not require
disclosure because it is irreversible, does not add a
foreign substance, [and] is readily detectable with a
loupe (Shor, 1996b). The organization also noted
that the GIA Gem Trade Laboratory, which does
not grade diamonds infused with a foreign substance, will grade lasered diamonds (with a notation
of the treatment on the report).
The FTC came down on the side of the diamond
industry and ruled that permanent, irreversible
treatments such as laser drilling did not have to be
disclosed to the consumer. This prompted protests
from a number of retailer and consumer organizations. Immediately after the ruling, the DMIA
reversed its position, fearing a consumer backlash,
and lobbied forcefully for a change in the Guides
(FTC, 1997). The industry, through the World
Federation of Diamond Bourses and the
International Diamond Manufacturers Association,
then adopted a disclosure requirement.
The issue of disclosure of permanent, nonreversible treatments surfaced even more strongly in
1999, when LKI subsidiary Pegasus Overseas Ltd.
and General Electric Co. jointly announced they
would be marketing diamonds whose color had
been enhanced by a high pressure/high temperature (HPHT) process (figure 19) that would be
FALL 2005
223
SYNTHETICS
Although Sumitomo Corp. of Japan introduced jewelry-sized gem-quality synthetic diamonds in the
mid-1980s, the company focused their efforts on
industrial applications. Gem-quality synthetics
were also produced, on an experimental basis, by
both De Beers and facilities in the former Soviet
Union. However, no producer offered synthetics on
a commercial scale until 2003, when Gemesis Corp.
of Sarasota, Florida, announced that it would market a line of yellow synthetic diamonds created by
the HPHT process, using a refinement of Russian
technology. Gemesis targeted retailers, marketing
its product at various international trade shows.
After an aborted effort in the early 1990s, Chatham
Created Gems re-entered the synthetic diamond
market in 2004 with a new supplier (Shigley et al.,
2004; figure 20). Both organizations are currently
partnering with jewelry designers to offer finished
jewelry as well as loose gems.
224
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225
226
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Total DTC
sales
India's
share
% of
DTC sales
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
4,167
3,927
3,417
4,366
4,250
4,531
4,834
4,640
3,345
5,240
5,670
4,454
5,154
5,518
5,695
638
678
566
706
690
747
677
618
483
777
995
989
1,127
1,469
1,608
15
17
17
16
16
16
14
13
14
15
18
22
22
27
28
Source: DTC sale... (2005). Note that this chart does not include
the substantial amounts of DTC rough that are transshipped
through Antwerp.
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227
228
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FUTURE OPPORTUNITIES
AND CHALLENGES
The DTCs stated policy of pushing more marketing
initiatives to build demand and the luxury image of
diamonds will undoubtedly continue to affect the
diamond market. Although new mine production
will likely meet rising consumer demand in the long
run, shortages of rough diamonds in certain size and
quality categories will remain for some time. Rough
and polished prices may become more volatile
because the DTC, Alrosa, Rio Tinto, Debswana, and
Namdeb have sold most of their buffer stocks, reducing their ability to mitigate supply shortages and
influence prices. In addition, competition between
FALL 2005
229
230
CONCLUSION
The last 15 years have brought changes to the diamond industry that have affected every part of the
pipeline, from mine to retail. As new diamond
sources opened up, De Beerss single-channel marketing system, in place since the 1930s, gave way to
a multi-channel environment. This required that
the company transform itself into a more marketing-driven business. It also ended its traditional role
FALL 2005
REFERENCES
Acohido B. (2003) He turned web site in the rough to online
jewel. USA Today, Oct. 20, p. B05.
Alrosa (2002) 2002 Annual Report of Alrosa. Moscow.
Argyle expansion costs jump (2005) Antwerp Facets On-line,
www.antwerpfacets.com/newsagency/detail.aspx?NewsletterID=
99&NewsletterItemID=965, June 21.
Austin G.T. (1994) Gemstones. In Minerals Yearbook, Vol. I.
Metals and Minerals, U.S. Geological Survey, Denver, CO,
pp. 31.131.7.
Average price of rough diamonds imported into india and polished
diamonds exported from India (2005) Gem and Jewellery Export
Promotion Council, www.gjepc.org/gjepc/gjepc.aspx?inclpage=
Uinfo_St_Statistics§ion_id=6#/.
Balazik R.F. (1995) Industrial diamond. In Minerals Yearbook,
Vol. I. Metals and Minerals, U.S. Geological Survey, Denver,
CO, pp. 23.123.3.
Belgian Association of Dealers, Importers, Exporters of
Polished Diamonds (2005) Press release, www.bvgd.be/user/en/
newscontent.php?id=137, July 14.
Benson S. (2005) The next African revolution. New York
Diamonds, No. 86, pp. 4046.
Beres G. (2004) TV Shopping. Whos Who in the Majors,
National Jeweler supplement, Feb. 1, p. 18.
Berman P., Goldman L. (2003) The man who cracked De Beers.
Forbes, Sept. 15, pp. 109116.
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231
232
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233
In the last decade, progress in diamond growth by chemical vapor deposition (CVD) has resulted in
significant improvement in the quality of synthetic single crystals. This article reports on the gemological and spectroscopic features of six synthetic type IIa diamonds grown for research purposes at
the French Laboratoire dIngnierie des Matriaux et des Hautes Pressions (LIMHP-CNRS), and
compares their diagnostic features to CVD-grown diamonds from other producers. Three of the six
samples were nitrogen doped, whereas the other three were classified as high purity. A number of
characteristics that are diagnostic of CVD synthetic diamond were present in the nitrogen-doped
crystals, despite an absence of defect-related absorption features in the infrared region. Identification
of the high-purity samples was more complicated, but it was still possible based on features in their
photoluminescence spectra, their distinctive birefringence, and characteristic luminescence images.
234
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235
Description
N2 doping Weight
during growth (ct)
Size (mm)
Color
Fluorescence in the
UV
DiamondView
fluorescence b
Nitrogen doped
67404
Free standing
Very low
0.81
Inert
66875
Free standing
Low
0.41
Inert
66669
Free standing
Medium
0.31
Inert
None
0.40
66876
About 0.3 mm
thick, over HPHT
synthetic diamond
substrate
Free standing
None
0.14
Inert
Blue
67405
Free standing
None
0.18
Inert
High purity
66675
a
b
Near colorless
(over yellow
substrate)
nd
formed on this sample. To avoid surface contamination, we cleaned the samples thoroughly with acetone in an ultrasonic bath. Low-temperature PL
spectra were recorded for all six samples using a
Renishaw 1000 Raman microspectrometer with an
Ar-ion laser at two different laser excitations: 488.0
nm (for the range 490950 nm) and 514.5 nm (for the
range 517 950 nm). PL spectra in the range
6401000 nm also were collected using a He-Ne
laser (632.8 nm) for the five samples that had their
substrate removed. In addition, PL spectra for one
sample (no. 67405) were obtained using a diode laser
(780.0 nm) for the range 7821000 nm. Several excitation lasers were used to cover as broad an emission-energy region as possible. The samples were
cooled by direct immersion in liquid nitrogen. Up to
three scans were accumulated in some cases to
achieve a better signal-to-noise ratio.
Infrared absorption spectra were recorded in the
mid-IR (6000400 cm-1, 1.0 cm-1 resolution) and
near-IR (up to 11000 cm-1, 4.0 cm-1 resolution)
regions at room temperature with a Thermo-Nicolet
Nexus 670 Fourier-transform infrared spectrometer
equipped with KBr and quartz beam splitters. A 6
beam condenser focused the incident beam on the
sample, and a total of 1,024 scans (per spectrum)
were collected to improve the signal-to-noise ratio.
UV-Vis-NIR absorption spectra were recorded
236
with a Thermo-Spectronic Unicam UV500 spectrophotometer over the range 250850 nm with a
sampling interval of 0.1 nm. The samples were
mounted in a cryogenic cell and cooled using liquid
nitrogen.
All the samples also were examined using a
Diamond Trading Company (DTC) DiamondView
deep-ultraviolet (<230 nm) luminescence imaging
system (Welbourn et al., 1996).
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UV-Vis-NIR
Increase in absorption
to high-energy side;
737 nm
No features
No features
nd
Photoluminescence
features
503.5, 563.3, 596/
597, 575, 637, 737,
766.1, 840.7 nm
503.5, 575, 596/597,
637, 699, 737 nm
503.5, 540.7, 563.3,
575, 596/597, 637,
737 nm
503.2, 503.5, 575,
596/597, 637, 699,
737 nm
No defect-related No features
737 nm
features
No defect-related Broad band at ~261 nm 737, 953 nm
features
The main (100) growth surface of the nitrogendoped samples invariably showed sequences of
micro-steps with relatively flat terrace regions
separated by inclined risers. This phenomenon is
known as step-bunching, and the corresponding features have been referred to as growth steps (de
Theije et al., 2000; Martineau et al., 2004). It was
observed on all the nitrogen-doped samples (figure
3), and also on portions of high-purity sample 66675
(figure 4). But in the latter case, since no nitrogen
was intentionally added, the higher methane concentration present during growth was probably
responsible for the surface growth features observed.
Anomalous birefringence, caused by residual
internal strain, is a useful feature for the identification of CVD synthetic diamond (see, e.g., Wang et
al., 2003; Martineau et al., 2004). Similar to many of
the Apollo products examined, the CVD synthetic
diamond crystals from LIMHP-CNRS displayed
cross-hatched bands of low-order interference colors
when viewed through the (100) face (figure 5A).
Small areas of localized strain with relatively higher
order interference colors surrounding tiny defect
centers also were observed. Much higher order
interference colors were seen at the four corners in
sample no. 66875 (figure 5B), and outside the substrate window in sample 66876 (figure 5C), indicating strong residual internal strain and accumulated
dislocations in these regions.
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237
Figure 3. Differential interference contrast microscopy revealed sequences of growth steps with terrace regions separated by inclined risers on the (100) surface of the nitrogen-doped CVD synthetic diamonds (left, no. 67404; right,
no. 66875). Photomicrographs by Alexandre Tallaire; magnified 50.
An outstanding feature evident from the anomalous birefringence is that bundles of dislocations
nucleated along the boundary between the substrate
and its CVD synthetic diamond overgrowth and are
uniformly parallel to the growth direction, as first
pointed out by Martineau et al. (2004). As a result, the
shadow of the substrate can be clearly seen in the
birefringence image, even after its removal. This feature was observed in all crystals except for no. 66669.
Figure 4. With a gemological microscope, portions
of this high-purity CVD synthetic diamond (no.
66675) display surface growth features similar to
those observed on the nitrogen-doped crystals. The
apparent color is caused by the yellow substrate of
HPHT synthetic diamond, which was not removed.
Photomicrograph by W. Wang; image width is
approximately 2.9 mm.
238
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Figure 5. The high-purity crystal in image A (no. 66876), which measures 4.4 mm across, displays the characteristic
strain pattern of a CVD-grown diamond when viewed perpendicular to a cubic crystal face (100). The shadow of
the substrate is clearly visible even after its removal, as the large square with relatively lower order interference
colors in the center of the sample. Much higher order interference colors were observed at the four corners of nitrogen-doped sample no. 66875 (B, 6.3 mm across) and in the area outside the substrate shadow of sample no.
66876 (C, image width is 2.9 mm), indicating strong residual internal strain and accumulated dislocations in these
regions. Photos A and B by W. Wang, and photomicrograph C by Shane McClure; crossed polarizers.
Figure 6. In contrast to CVD synthetic diamonds, natural type IIa diamonds typically show banded and tatami
patterns with low first-order interference colors (A, B). HPHT-grown synthetic type IIa diamonds most commonly
show no strain (C). Photomicrographs by Christopher Smith; crossed polarizers.
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239
Figure 9. The CVD synthetic diamonds from LIMHPCNRS did not show any defect-related absorption in
the near-infrared range. In contrast, most Apollo
CVD synthetic diamonds examined by Wang et al.
(2003) displayed relatively strong absorptions in this
range. Of the five specimens examined, only the light
brown crystal (no. 67404) exhibited a very weak
absorption at 6856 cm-1 (not visible below). The spectra are shifted vertically for clarity.
240
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241
Figure 12. In the DTC DiamondView, the nitrogen-doped CVD-grown crystals showed a strong and characteristic
orange to orangy red luminescence (sample no. 66875, left). In contrast, the high-purity crystals showed only a
very weak blue fluorescence (sample no. 66876, right). The original positions of the substrates are visible as the
darker square-shaped patterns in the center of the images. The circular areas within the squares are from the
sample holder. Photos by W. Wang.
242
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natural type IIa diamonds. As in the aforementioned birefringence images, the original position
of the HPHT-grown synthetic substrate also was
observable in most DiamondView fluorescence
and phosphorescence images.
Natural type IIa diamonds usually show blue fluorescence in the DiamondView, and they typically
display characteristic mosaic networks of polygonized dislocations or dislocations lying in slip bands
(Martineau et al., 2004). A few natural type IIa diamonds exhibit orange luminescence, similar to that
of nitrogen-doped CVD synthetic diamonds. Our
extensive examinations have revealed that mosaic networks and slip bands are also the predominant features of natural type IIa diamonds that show
this orange fluorescence (figure 14).
IDENTIFICATION FEATURES
The CVD synthetic diamonds from LIMHP-CNRS
were produced solely for research purposes, but in
the event a similar product ultimately reaches the
gem market it is important to understand the differences between these samples and natural diamonds, as well as other gem-quality CVD synthetics currently being produced. Although the products examined in this study showed considerable
variation in color and purity, it is clear that deposition of non-diamond carbon during crystal growth
at relatively high growth rates can be minimized,
leading to the formation of near-colorless gemquality crystals. The relatively narrow thickness of
CVD overgrowth (no more than 1.64 mm in the
crystals examined) would limit their potential jewelry application to very small gems. However,
other manufacturers (Apollo Diamond, Element
Six, and the Carnegie Institute) have demonstrated
their ability to grow high-quality CVD crystals
thick enough to be faceted as gems. It is feasible
CONCLUDING REMARKS
CVD synthetic diamonds from LIMHP-CNRS have
been created solely for research purposes, as both
nitrogen-doped and high-purity samples. These
type IIa products showed considerable variation in
color and impurity concentration. This study
revealed some subtle but clear differences between
the LIMHP-CNRS products and the suite of Apollo
products examined by Wang et al. (2003) and the
Element Six products examined by Martineau et al.
(2004). While the LIMHP-CNRS synthetics show
almost no absorption features in the infrared
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243
niques, larger and better-quality synthetic diamonds are likely to be produced. Identification
features will probably change to some extent with
the continued development of CVD synthesis
techniques.
REFERENCES
Bates R. (2005) University claims better, faster synthetic diamonds. JCK, Vol. 176, No. 6, p. 51
Bergman L., Stoner B.R., Turner K.F., Glass J.T., Nemanich R.J.
(1993) Microphotoluminescence and Raman scattering study
of defect formation in diamond films. Journal of Applied
Physics, Vol. 73, No. 8, pp. 39513957.
Collins A.T., Kamo M., Sato Y. (1989) Optical centers related to
nitrogen, vacancies and interstitials in polycrystalline diamond films grown by plasma-assisted chemical vapour deposition. Journal of Physics D: Applied Physics, Vol. 22, No. 9,
pp. 14021405.
de Theije F.K., Schermer J.J., van Enckevort W.J.P. (2000) Effects
of nitrogen impurities on the CVD growth of diamond: Step
bunching in theory and experiment. Diamond and Related
Materials, Vol. 9, No. 8, pp. 14391449.
King J.M., Moses T.M., Shigley J.E., Liu Y. (1994) Color grading of
colored diamonds at the GIA Gem Trade Laboratory. Gems &
Gemology, Vol. 30, No. 4, pp. 220242.
King J.M., Moses T.M., Shigley J.E., Welbourn C.M., Lawson
S.C., Cooper M. (1998) Characterizing natural-color type IIb
blue diamonds. Gems & Gemology, Vol. 34, No. 4, pp.
246268.
Martineau P.M., Lawson S.C., Taylor A.J., Quinn S.J., Evans D.J.F.,
Crowder M.J. (2004) Identification of synthetic diamond grown
using chemical vapor deposition (CVD). Gems & Gemology,
Vol. 40, No. 1, pp. 225.
Moses T.M., Shigley J.E., McClure S.F., Koivula J.I., Van Daele M.
(1999) Observations on GE-Processed Diamonds: A photographic record. Gems & Gemology, Vol. 35, No. 3, pp. 1422.
Shigley J.E., Fritsch E., Stockton C.M., Koivula J.I., Fryer C.W.,
Kane R.E. (1986) The gemological properties of the Sumitomo
gem-quality synthetic yellow diamonds. Gems & Gemology,
Vol. 22, No. 4, pp. 192208.
Shigley J.E., Fritsch E., Stockton C.M., Koivula J.I., Fryer C.W.,
Kane R.E., Hargett D.R., Welch C.W. (1987) The gemological
properties of the De Beers gem-quality synthetic diamonds.
Gems & Gemology, Vol. 23, No. 4, pp. 187206.
Shigley J.E., Moses T.M., Reinitz I., Elen S., McClure S.F., Fritsch E.
244
(1997) Gemological properties of near-colorless synthetic diamonds. Gems & Gemology, Vol. 33, No. 1, pp. 4253.
Shigley J.E., Abbaschian R., Clarke C. (2003) Gemesis laboratorycreated diamonds. Gems & Gemology, Vol. 38, No. 4, pp.
301309.
Shigley J.E., McClure S.F., Breeding C.M., Shen A., Muhlmeister
S.M. (2004) Lab-grown colored diamonds from Chatham
Created Gems. Gems & Gemology, Vol. 40, No. 2, pp.
128145.
Smith C.P., Bosshart G., Ponahlo J., Hammer V.M.F., Klapper H.,
Schmetzer K. (2000) GE POL diamonds: Before and after.
Gems & Gemology, Vol. 36, No. 3, pp. 192215.
Steed J.W., Davis T.J., Charles S.J., Hayes J.M., Butler J.E. (1999)
3H luminescence in electron-irradiated diamond samples and
its relationship to self-interstitials. Diamond and Related
Materials, Vol. 8, No. 10, pp. 18471852.
Tallaire A., Achard J., Sussmann R.S., Silva F., Gicquel A. (2005)
Homoepitaxial deposition of high-quality thick diamond
films: Effect of growth parameters. Diamond and Related
Materials, Vol. 14, No. 37, pp. 249254.
Wang W., Moses T., Linares R., Shigley J.E., Hall M., Butler J.E.
(2003) Gem-quality synthetic diamonds grown by the chemical vapor deposition method. Gems & Gemology, Vol. 39,
No. 4, pp. 268283.
Welbourn C.M., Cooper M., Spear P.M. (1996) De Beers natural
versus synthetic diamond verification instruments. Gems &
Gemology, Vol. 32, No. 3, pp. 156169.
Yan C.-S., Vohra Y.K., Mao H.-K., Hemley R.J. (2002) Very high
growth rate chemical vapor deposition of single-crystal diamond. Proceedings of the National Academy of Sciences of the
United States of America, Vol. 99, No. 20, pp. 1252312525.
Yan C.-S., Chen Y.-C., Ho S.-S., Mao H.-K., Hemley R.J. (2005)
Large single crystal CVD diamonds at rapid growth rates.
Abstracts of the 8th Applied Diamond Conference/
NanoCarbon 2005, May 1519, Argonne National Laboratory,
Argonne, Illinois.
Zaitsev A.M. (2001) Optical Properties of Diamond. SpringerVerlag, Berlin, 502 pp.
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BACKGROUND
Solid, vapor, and fluid inclusions in transparent gem
rhodonite crystals from Broken Hill, New South
Wales, Australia, have been identified for the first
time using Raman spectroscopy and gemological/
petrographic techniques. Among the solid inclusions are sphalerite, galena, quartz, and fluorite. The
rhodonite also contained hollow needle-like tubes
and negative rhodonite crystals. Three-phase inclusions were found to contain a saline liquid, a
gaseous mixture of nitrogen (N2) and methane
(CH4), and ilmenite crystals.
246
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Most of the orebodies at Broken Hill have a granular texture in both non-ore (gangue) and sulfide portions. Specimens of ore collected from 3 Lens, one of
the two known lead lodes at North mine, typically
display this texture (figure 4). Local geologists refer to
the lead lodes as having layering in the ore, known to
enclose pods and boudins (sausage-shaped segments) of low-grade rhodonite, bustamite or manganhedenbergite, other gangue minerals, and sulfides.
Overall, masses of rhodonite and bustamite have
exceeded 20 m across (Maiden, 1975).
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247
Transparent
rhodonite
crystals
10 mm
248
Galena
Average
rhodonite
FALL 2005
inclusion identification. The thickness of the sections ranged from 100 m to 2 mm, and most contained subsurface solid or fluid inclusions ranging
from <1 m to 100 m in diameter. One crystal,
specimen 3, was retained intact for the duration of
the experimental work. We determined gemological
properties (including visible absorption spectra)
using standard gemological instruments on specimen 2, a faceted stone (figure 7). (Specimen 1 was
the ore sample shown in figure 4.)
Figure 7. Gemological properties were taken on this
0.86 ct faceted rhodonite (5.4 5.4 3.9 mm; specimen 2) from the North mine at Broken Hill, which
was cut by Ralph Westen. Photo by Paul Millsteed.
FALL 2005
249
tially pinpointed using transmitted light were targeted by focusing the laser beam via the 50 microscope objective.
Raman spectra for the vapor phase of three-phase
inclusions were also recorded in situ for one of the
sections cut from specimen 4 using a Dilor
SuperLabram microspectrometer. These inclusions
were analyzed with a higher-energy 514.5 nm laser
excitation. A 100 microscope objective was used to
increase the laser intensity at the focal point within
the inclusions. The spectra of the vapor phase were
recorded from 3800 to 1000 cm1 using a single 20second integration time per spectrum. The detection limits for specific gases are dependent on the
250
FALL 2005
Figure 10. Many samples also contained subangular elongate sphalerite inclusions, such as
those shown here in specimen 7. Photomicrograph
by Paul Millsteed.
RESULTS
Gemological Properties. The refractive indices
determined from specimen 2 were n = 1.732 and n
= 1.745. Pleochroism was generally weak, showing
colors of yellowish red, pinkish red, and pale yellowish red. The optic axis angle (2V) yielded a biaxial positive optic sign. The dominant morphological
FALL 2005
251
DISCUSSION
The gemological properties obtained in this study
were consistent with those for rhodonite in the literature, although the R.I. values were higher than
those given by Diehl and Berdesinski (1970) and
Bank et al. (1973a). While pyroxmangite is recognized from Broken Hill, all the specimens reported
here have typical rhodonite compositions and
properties.
252
This study identified a diverse group of inclusions in transparent gem rhodonite from the North
mine at Broken Hill. Previous studies of gem
rhodonite from this locality (Diehl and Berdesinski, 1970; Bank et al., 1973a,b and 1974; Gaines
et al., 1997) have not mentioned the presence of
inclusions.
The basic gemological properties of Brazilian
rhodonite appear to be comparable to those of
rhodonite from Broken Hill. Faceted rhodonite from
Minas Gerais, Brazil, was recently found to contain
curved needles, fingerprints, and two-phase inclusions (Quinn, 2004), but no solid inclusions were
identified.
We believe that the inclusions in the Broken Hill
rhodonite originate from metamorphic reactions
that may have produced fluids through processes of
dehydration and decarbonation (Stevenson and
Martin, 1986). It is probable that partial melting and
plastic flow of the sulfides occurred in the Broken
Hill ore deposit during peak metamorphism
(Maiden, 1976), which may be evidence of hightemperature fluid activity (Plimer, 1979).
Experimental studies of the PbS-FeS-ZnS-Ag2S
system by Mavrogenes et al. (2001) showed that
eutectic melting of sulfide occurs between 772 and
830C. In the Broken Hill region, metamorphism
was accompanied by folding, which changed the
original structure, texture, and mineralogical content of the Broken Hill ore deposit. While the sulfide minerals galena and sphalerite have an average
grain size of 34 mm (Birch, 1999), microscopic
pyrrhotite and other sulfide inclusions have also
been trapped within the silicate mineralogy, including gem rhodonite. The presence of pyrrhotite in
rhodonite supports the eutectic peak metamorphic
conditions discussed.
The three-phase (saline liquid, CH4-N2 vapor,
and ilmenite crystal) inclusions are considered
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253
CONCLUSIONS
Sphalerite, galena, quartz, fluorite, and rare grains
of pyrrhotite have been identified as solid inclusions in gem rhodonite from the Broken Hill area
in New South Wales, Australia. Also identified for
the first time in this material is a suite of threephase (fluid, vapor, and solid) inclusions. These
inclusions have trapped the products of dehydration, decarbonization, and partial melting during
REFERENCES
Albrecht J., Peters T. (1980) The miscibility gap between
rhodonite and bustamite along the join MnSiO 3
Ca0.60Mn0.40SiO3. Contributions to Mineralogy and Petrology,
Vol. 74, pp. 261269.
Bank H., Berdesinki W., Diehl R. (1973a) Durchsichtiger Rhodonit aus Broken Hill/Australien. Zeitschrift der Deutschen
Gemmologischen Gesellschaft, Vol. 22, No. 3, pp. 101103.
Bank H., Berdesinki W., Diehl R. (1973b) Durchsichtiger rtlicher
Pyroxmangit aus Broken Hill/Australien und die Mglichkeiten seiner Unterscheidung von Rhodonit. Zeitschrift der
Deutschen Gemmologischen Gesellschaft, Vol. 22, No. 3, pp.
104110.
Bank H., Berdesinki W., Ottermann J., Schmetzer K. (1974)
Transparent red iron rich rhodonite from Australia. Zeitschrift der Deutschen Gemmologischen Gesellschaft, Vol. 23,
No. 3, pp. 180188.
Barnes R.G. (1986) A summary record of mineral deposits in the
Broken Hill block, excluding the southeastern portion.
Records of the Geological Survey of New South Wales, Vol.
22, No. 2, pp. 1367.
Birch W.D. (1999) The Minerals of Broken Hill. Broken Hill City
Council and Museum, Victoria, New South Wales.
Diehl R., Berdesinski W. (1970) Twinning in pyroxmangite from
the North mine in Broken Hill, New South Wales, Australia.
Neues Jahrbuch fr Mineralogie Monatshefte, Vol. 1970, No.
8, pp. 348362.
Gaines R.V., Skinner H.C.W., Foord E.E., Mason B., Rosenzweig
A., King V.T. (1997) The System of Mineralogy of James
Dwight Dana and Edward Salisbury Dana, 8th ed. John
Wiley & Sons, New York, pp. 13261328.
Johnson I.R., Klingner G.D. (1975) The Broken Hill ore deposit
and its environment. In C.L. Knight, Ed., The Economic
Geology of Australia and Papua New Guinea, Australasian
Institute of Mining and Metallurgy, Melbourne, pp. 476491.
Koenig K. (1983) Broken Hill: 100 Years of Mining. New South
Wales Department of Mineral Resources, Sydney.
Maiden K.J. (1975) High grade metamorphic structures in the
Broken Hill orebody. Australian Institute of Mining and
254
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EDITORS
Thomas M. Moses and Shane F. McClure
GIA Laboratory
CONTRIBUTING EDITORS
G. Robert Crowningshield
GIA Laboratory, East Coast
Cheryl Y. Wentzell
GIA Laboratory, West Coast
Unusual SYNTHETIC
ALEXANDRITE
Magnification is traditionally the key
method in the separation of natural
and synthetic gemstones. Standard
gemological tests such as refractive
index, optic character, optic figure,
and pleochroism are generally not useful in making this separation, since
by definitionto be a synthetic, a
stone must have essentially the same
optical, chemical, and physical properties as its natural counterpart. In some
cases, however, the internal scene can
be very misleading, so more advanced
tests are necessary to prove natural or
synthetic origin.
Recently, a 4.62 ct transparent
blue-green oval modified brilliant
(11.04 8.99 6.32 mm) was submitted to the East Coast laboratory for
identification. The specimen exhibit-
that the gem was a melt-grown synthetic. Unfortunately, the gas bubbles were so small that their identity
could not be confirmed with a gemological microscope; it was possible
that they were simply minute included crystals.
To observe the growth structure,
we immersed the sample in methylene iodide and viewed it in diffuse
transmitted light. As evident in figure 3, a very subtle S-shaped curved
growth zoning was present. This, too,
was indicative of a melt synthetic.
256
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DIAMOND
Dyed Rough
The East Coast laboratory is occasionally asked to examine diamond rough
prior to cutting. Recently, we received
two diamond crystals, both with
requests to determine whether their
color was natural or the result of treatment. One crystal was approximately
half a carat, and the second was about
one carat. Both had worn edges and
generally frosty surfaces with small,
evenly distributed, crescent-shaped
fractures and a few larger indentations. In reflected light, the smaller
crystal appeared to be blue-green (fig-
LAB NOTES
Figure 4. These diamond crystals were submitted to the East Coast laboratory for origin-of-color determinations. Although the approximately half-carat
diamond appeared blue-green when examined in reflected light (top left),
transmitted light revealed its true yellow bodycolor (top right). The approximately 1 ct crystal appeared blue in reflected light (bottom left), while in
transmitted light it was greenish gray (bottom right).
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Figure 6. The larger rough diamond also showed dye concentrations on its surface. The small
indentations contained a dark
blue flaky dye, the shallow
cracks contained lighter blue dye
concentrations, and spots of an
even lighter blue were seen on the
surface itself. Magnified 45.
258
LAB NOTES
Figure 7. These two strongly colored Fancy Deep blue diamonds (0.71 ct, left;
1.04 ct, right) showed some unusual characteristics in addition to their color.
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Figure 9. The mid-IR spectrum of the 1.04 ct round brilliant shows complete saturation in the region of the boron features, reflected in the neartotal absorption above ~2000 cm -1. Also present is the 1332 cm-1 intrinsic
diamond peak; the assignment of the peak at 1290 cm-1 is unknown.
Figure 10. The PL spectra of the two diamonds reflect the relative
strength of their red phosphorescence. The emission peak at 776.5 nm for
the 0.71 ct octagonal brilliant, with its strong red reaction, is of greater
intensity than that for the 1.04 ct round brilliant (with its weaker purplish blue phosphorescence). The spectrum of a diamond with blue phosphorescence usually does not show 776.5 nm emission. (The diamond
Raman peak at 1332 cm -1, which occurs in the PL spectrum at 521.9 nm,
is normalized to the same intensity for the three spectra.)
PEARLS
Large Natural Freshwater
Pearl from Texas
The GIA Laboratory has previously
reported on natural pink freshwater
pearls from the Concho River northwest of Austin, Texas (Summer 1989
Gem News, p. 115), and the lakes and
rivers in the San Angelo area of west
Texas (Fall 1990, pp. 223 224).
Recently, another attractive pink
LAB NOTES
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259
260
LAB NOTES
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Figure 13. The first X-radiograph of the pearl in figure 12 exposed what appeared to be a spherical core that is
slightly darker than the outer nacre layers (left). Another radiograph taken 90 to the first revealed a slightly
asymmetrical oval outline (center) and natural features (right).
Figure 14. These large baroque South Sea cultured pearls (38.30 and 40.55
ct) are unusual for their size and quality.
SYNTHETIC TURQUOISE
Necklace
Introduced to the industry in 1972,
Gilson synthetic turquoise can be recognized by its characteristic cream of
wheat texture, which appears with
magnification as bluish spheroids in a
light colored groundmass (figure 15,
left). Although distinctive to most
gemologists, it is not dramatically different from the texture seen in some
natural turquoise (figure 15, right), the
difference being more in the uniformi-
LAB NOTES
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261
Figure 16. This graduated strand of 45 round greenish blue beads (1416
mm) proved to be synthetic turquoise.
262
LAB NOTES
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qualitative data suggested that yttrium, which is used to stabilize manufactured CZ at room temperature, was
present in what appeared to be a
greater quantity than Zr. There was
also a trace of hafnium. CZ typically
contains significantly less Y than Zr,
which raised the question of whether
this was CZ with a large amount of
stabilizer, or another material altogether. Analysis of phase diagrams
(e.g., R. Roth et al., Phase Diagrams
for Ceramists, American Ceramic
Society, Columbus, Ohio, 1981, Vol.
4, pp. 141142 and 1987, Vol. 6, pp.
182184), as well as various texts (e.g.,
K. Nassau, Gems Made by Man,
Chilton Book Co., Radnor, PA, 1980,
p. 240) indicated that in fact CZ can
contain slightly more yttrium than
zirconium.
The possibility that our sample
might be one of these CZs with
excessive stabilizer was supported by
a further literature search, which indi-
Figure 17. The mid-IR spectral features of natural turquoise are noticeably
sharper than those for the synthetic material. Spectra have been offset for
clarity. (Modified from E. Fritsch and C. Stockton, Infrared spectroscopy
in gem identification, Spring 1987 Gems & Gemology, p. 22.)
Figure 18. Resembling a highquality zircon, this intensely colored greenish blue gem (19.66 ct)
is a manufactured product, yttrium zirconium oxide.
PHOTO CREDITS
Wendi Mayerson1 and 2; Elizabeth
Schrader3 and 7; Carolyn van der Bogert
46; Wuyi Wang8; C. D. Mengason11,
12, and 18; Cheryl Wentzell13; Jessica
Arditi14; Shane McClure15 (right);
Maha Calderon15 (left) and 16.
LAB NOTES
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263
EDITOR
Brendan M. Laurs (blaurs@gia.edu)
CONTRIBUTING EDITORS
Emmanuel Fritsch, IMN, University of
Nantes, France (fritsch@cnrs-imn.fr)
Henry A. Hnni, SSEF, Basel, Switzerland
(gemlab@ssef.ch)
Franck Notari, GIA, Geneva, Switzerland
(franck.notari@gia.edu)
Kenneth V. G. Scarratt, GIA, Bangkok, Thailand
(kscarratt@aol.com)
Christopher P. Smith, GIA Laboratory,
New York (chris.smith@gia.edu)
DIAMONDS
Gem mosaics of faceted diamonds. Mosaic artwork constructed from gem materials has typically used rough fragments or tumbled/polished pieces of colored stones.
However, until now this contributor was unaware of the
use of faceted fancy-color diamonds to create gem
mosaics. During a recent trip to Brazil, several examples of
this new artwork, referred to as Diamond Craft (figure 1),
were shown to her by Jorge Brusa (Bristar, Sao Paulo).
Mr. Brusa began experimenting with the concept in
Figure 1. This Diamond Craft gem mosaic after one of
Vincent van Goghs Bedroom paintings measures
10 10 cm and was created with 5,482 fancy-colored
faceted diamonds, with a total weight of 46.32 ct.
Courtesy of Bristar.
Editors note: The initials at the end of each item identify the
editor or contributing editor who provided it. Full names and
affiliations are given for other contributors. Shane F. McClure,
Dr. Mary L. Johnson, and Dr. James E. Shigley of the GIA
Laboratory in Carlsbad are thanked for their internal review of
the Gem News International section.
Interested contributors should send information and
illustrations to Brendan Laurs at blaurs@gia.edu (e-mail),
760-603-4595 (fax), or GIA, 5345 Armada Drive, Carlsbad,
CA 92008. Original photos will be returned after consideration or publication.
GEMS & GEMOLOGY, Vol. 41, No. 3, pp. 264278
2005 Gemological Institute of America
264
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Figure 2. Microscopic examination of a 5.37 ct emerald showed alternating color bands with subtle conical growth features on the edges of the color zones.
Photomicrograph by G. Choudhary; magnified 35.
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265
Figure 5. A comparison
of the infrared spectrum
of the 5.37 ct emerald
with that of a Russian
hydrothermal synthetic
emerald shows differences in the absorption
bands between 4000
and 3000 cm -1 and in
the intensity of the peak
at around 5270 cm -1.
The IR absorption features shown by the 5.37
ct emerald are indicative of natural origin.
266
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268
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fingerprint inclusions. They exhibited weak-to-moderate red fluorescence to long-wave UV radiation, and weak
red or no fluorescence to short-wave UV. Typical features
seen with a desk-model spectroscope included a weak
absorption band at 460 nm, a 475/480 nm doublet, and a
band at 670 nm.
Although the colors of some of these samples resemble
those seen in sapphires treated by Be diffusion, the samples showed no evidence of the high temperatures used in
that process. According to Mr. Blauwet, much of this
Indian sapphire is being sold on the market as heated Sri
Lankan or Madagascar material.
Shane F. McClure (smcclure@gia.edu)
GIA Laboratory, Carlsbad
James E. Shigley
GIA Research, Carlsbad
BML
Tenebrescent scapolite from Afghanistan. At the 2004
Tucson Gem shows, gem and mineral dealer Herb Obodda
(H. Obodda, Short Hills, New Jersey) showed GIA personnel several rough and cut pieces of a colorless gem material from Badakhshan, Afghanistan, that was thought to be
hackmanite on the basis of its reversible photochromism
(or tenebrescence, a property in which some minerals
darken in response to radiation of one wavelength and
then reversibly lighten on exposure to a different wavelength). When charged under Mr. Oboddas strong UV
source, the stones turned blue. When they were exposed to
daylight or a strong incandescent light source, the color
faded completely in seconds.
Mr. Obodda obtained the rough material during buying trips to Pakistan in early 2003 through early 2004. He
said that the local dealers have habitually referred to the
colorless sodalite from Badakhshan as hackmanite
Figure 14. Remarkable tenebrescent behavior was exhibited by these scapolites (0.915.17 ct) from Afghanistan.
The stones turned blue when exposed to short-wave UV radiation for approximately one minute, and faded to
colorless within seconds when brought into light. Courtesy of H. Obodda; photos by C. D. Mengason.
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270
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George R. Rossman
California Institute of Technology
Pasadena, California
James E. Shigley
GIA Research, Carlsbad
BML
INCLUSIONS IN GEMS
Medusa quartz with gilalite inclusions. Gem-quality
quartz crystals containing interesting blue-to-green inclusions were discovered in Paraba State, Brazil, in August
2004. Since then, about 10 kg have been extracted by
local miners.
Several samples of this quartz were studied by these contributors, including some well-formed crystals, broken fragments, and cabochons. The quartz crystals were up to 10 cm
long and exhibited striking color zoning: a few crystallographically oriented layers of light purple amethyst in otherwise colorless rock crystal, as well as distinct layers of eyevisible blue-to-green inclusions. Some of these blue-to-green
inclusions occurred in the colorless cores of the crystals (figure 17); they were less than a millimeter in longest dimension, with shapes reminiscent of jellyfish (figure 18). All of
these inclusions were located on the same growth plane, and
each consisted of a cluster of very thin radiating fibers. The
jellyfish-like inclusions were often color zoned, varying from
light green to a vivid greenish blue, with some layers being
nearly white (again, see figure 17). The overall appearance,
similar to a floating colony of jellyfish, suggests the name
medusa quartz, after the typical bell-shaped appearance of
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271
TREATMENTS
Natural pearl with orient-like coating. Recently, the
SSEF Swiss Gemmological Institute received for testing
a parcel of 13 loose button-shaped pearls weighing about
272
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6 ct each. They showed moderate to good luster and orient, and ranged from white to light cream. X-radiographs revealed that all were natural pearls, showing
characteristic structures such as concentric circles, fine
fissures, and darker central zones. Using X-ray luminescence (see H. A. Hnni et al., X-ray luminescence, a
valuable test in pearl identification, Journal of
Gemmology, Vol. 29, No. 5/6, 2005, pp. 316324), elevated Mn contents were noted in three of the samples,
indicating that they were freshwater pearls, while the
remainder were of saltwater origin.
Careful examination of one of the saltwater pearls (figure 22, left) revealed a somewhat patchy appearance and
an unusual sticky surface. With magnification, a shiny
coating was evident. The coating was transparent (with
tiny trapped air bubbles) and contained minute reflective
particles. When examined with a fiber-optic light, the
pearl displayed a dotted texture similar to that seen in
imitations. The coating was partially chipped off in spots
(figure 23), which explained the patchy color distribution.
Although not visible in figure 23, the surface of these
exposed areas showed distinct polish marks.
When exposed to long-wave UV radiation, the pearl
fluoresced dull yellowexcept in areas where the coating
was chipped off, in which the pearl surface fluoresced
strong white. The reaction to short-wave UV was similar
but less distinct.
Chemical analysis by EDXRF spectroscopy revealed a
low concentration of Bi and traces of Sr. Bi has not been
detected so far in any untreated pearl. Raman analyses of
the coating with a 514 nm Ar laser were compared with
spectra from the underlying pearl surface. The spectrum of
the coating showed a distinct peak at 1602 cm-1, in addition to the characteristic Raman peaks for aragonite. The
1602 cm-1 peak is indicative of an artificial resin.
Based on these observations, this contributor suspects
Figure 21. These rock crystal cabochons (approximately 5 cm long) from Brazil contain fake inclusions
that were apparently created in a three-step process.
In addition, the cabochon in the center contains
reflective oval fractures that were likely induced by
thermal shock. The cabochon on the right shows the
base, which is covered with a mixture of glue and
mineral powder. Photo by J. Hyrsl.
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273
Figure 24. These two stones (9.61 and 11.40 ct) proved
to be fibrolite (sillimanite) that had been dyed and
impregnated to imitate ruby. Photo by S. Singbamroong, Dubai Gemstone Laboratory.
274
CONFERENCE REPORTS
Applied Diamond Conference 2005. The 8th International
Conference on Applications of Diamond and Related
Materials was held May 1519 at Argonne National
Laboratory, Argonne, Illinois. The conference included several presentations of interest to gemologists. Abstracts are
available by downloading the Program Book from the conference Web site, http://nano.anl.gov/adc2005.
Dr. Mark Newton of the University of Warwick, U.K.,
and coauthors discussed two new hydrogen defects
(vacancy-hydrogen and vacancy-nitrogen-hydrogen complexes) in CVD synthetic diamonds, their spectroscopic
signatures, and their behavior during HPHT and low-temperature annealing. Dr. Peter Doering of Apollo Diamond,
Boston, Massachusetts, reviewed the effect of HPHT
treatment on defects and optical properties of single-crystal CVD synthetic diamond. In the question-and-answer
session, he stated that Apollo plans to release their CVD
synthetic diamonds into the gem market around the middle of 2006. Dr. Chih-Shue Yan and coauthors of the
Geophysical Laboratory, Carnegie Institution,
Washington, DC, described recent progress in growing
large single-crystal CVD synthetic diamonds. The
Carnegie group can now grow CVD synthetic diamonds
(figure 26) at a rate of 100 microns/hour (compared to a
traditional growth rate of 1 micron/hour) by using a
focused plasma beam. The maximum thickness of the
CVD layer achieved so far is 12 mm, and plates weighing
up to 10 ct have been grown. Some of their CVD synthetic diamonds also have been annealed by HPHT methods.
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276
MISCELLANEOUS
Historic U.S. sapphire and benitoite mines close. G&G
author Keith Mychaluk (Calgary, Alberta, Canada)
informed this contributor that the Vortex sapphire mine at
Yogo Gulch, Montana, closed in late November 2004.
According to Peter Ecker of Yogo Creek Mining (Hobson,
Montana), the sapphire ore had become much less friable
at depth (over 120 m), which made both the extraction and
processing of the ore less economic. In addition, the thickness of the lateral dike formation being mined had pinched
considerably. Most of the surface workings have been
reclaimed, and the remaining sapphire inventory has been
sold to Adair Jewelers in Missoula, Montana.
Also, this contributor has been informed by Bryan Lees
(The Collector's Edge, Golden, Colorado) that his company
permanently closed and reclaimed the Benitoite Gem
mine (San Benito County, California) in June 2005. He
indicated that both the lode and eluvial sources were commercially exhausted. A caretaker will remain on the property indefinitely to oversee the revegetation and dissuade
trespassers. Mr. Lees indicated that he will now focus
efforts on marketing the stockpile of benitoite gem rough
that his firm has accumulated over the past five years of
mining the property.
BML
ANNOUNCEMENTS
Conferences
Mineralien Hamburg. The International Show for Minerals,
Fossils, Precious Stones and Jewellery will take place in
Hamburg, Germany, on November 911, 2005. Special exhibitions will feature gems, jewelry, and mineral specimens
owned by Russias tsars, as well as Native American
turquoise. Visit www.hamburg-messe.de/mineralien.
Visit Gems & Gemology in Tucson. Meet the editors and
take advantage of special offers on subscriptions and back
issues at the G&G booth in the publicly accessible
Galleria section (middle floor) of the Tucson Convention
Center during the AGTA show, February 16, 2006.
GIA Educations traveling Extension classes will offer
FALL 2005
ERRATUM
The Winter 2004 Gem News International entry titled A
notable triplite from Pakistan reported that the stone
originated from the Shigar Valley in northern Pakistan, but
information recently obtained from a reliable local miner
indicates that the triplite came from the Namlook mine,
which is above the village of Dassu in the Braldu Valley,
also in northern Pakistan. We thank Dudley Blauwet for
bringing this update to our attention.
FALL 2005
277
This year, 236 dedicated readers participated in the 2005 GEMS & GEMOLOGY Challenge. Entries arrived from
all corners of the world, as readers tested their knowledge on the questions listed in the Spring 2005 issue.
Those who earned a score of 75% or better received a GIA Continuing Education Certificate recognizing their
achievement. The participants who scored a perfect 100% are listed below. Congratulations!
AUSTRALIA Grange, South Australia: Barbara Wodecki BELGIUM Diegem: Guy Lalous.
Diksmuide: Honor Loeters. Hemiksem: Daniel De Maeght. Koksijde: Christine Loeters. Overijse:
Margrethe Gram-Jensen. Ruiselede: Lucette Nols. Tervuren: Vibeke Thur BRAZIL Rio de Janeiro:
Luiz Angelo CANADA Bobcaygeon, Ontario: David Lindsay ENGLAND Hereford: Michael
Langford. London: Douglas Kennedy FRANCE Draveil: Claire Carpentier INDONESIA Jakarta:
Warli Latumena ITALY Ferrara: Sonia Franzolin. Padova: Marco Maso. Porto Azzurro: Diego
Trainini THE NETHERLANDS Rotterdam: E. Van Velzen POLAND Lublin: Marek A. Prus
SPAIN Valencia: Monika Bergel-Becker. Rocafort: Elvira Orts Rodriguez. Salou: Santigo Escol
SWEDEN Jarfalla: Thomas Larsson SWITZERLAND Lausanne: Thierry Christe THAILAND
Bangkok: Surachart Panjathammawit, Potjana Sawangjidr UNITED STATES Arizona Chandler:
LaVerne Larson. Cottonwood: Glenn Shaffer. Tucson: Molly Knox. Yuma: Crystal Young. Arkansas
Greenbrier: Beverly Brannan. California Burlingame: Sandra MacKenzie-Graham. Carlsbad: Abba
Steinfeld, Jim Viall, Lynn Viall, Philip York, Marisa Zachovay. Culver City: Veronica Clark-Hudson,
Judith Shechter-Lankford. Fremont: Ying Ying Chow. Fullerton: David Le Rose. Marina Del Rey:
Veronika Riedel. Oceanside: Kevin Nagle. Orange: Alex Tourubaroff. Pacifica: Diana Gamez. Rancho
Cucamonga: Sandy MacLeane. Redwood City: Starla Turner. Connecticut Vernon: Joe Thon Negs.
Florida Clearwater: Timothy Schuler. Deland: Sue Angevine Guess. Sun City: Jeanne Naish. Hawaii
Honolulu: Brenda Reichel. Makawao: Alison Fahland. Illinois Normal: William Lyddon. Indiana
Carmel: Mark Ferreira. Fishers: Laura Haas. Greenfield: Rachelle Kihlstrum. Indianapolis: Wendy
Wright Feng. Maryland Burtonsville: Jody Tebay. Gaithersburg: Marvin Wambua. Massachusetts
Uxbridge: Bernard Stachura. Missouri Perry: Bruce Elmer. New Jersey Clifton: Jason Darley. New
York Hawthorn: Lorraine Bennett. New York: Carolyn van der Bogert, HyeJin Jang-Green, Wendi
Mayerson, Anna Schumate. North Carolina Candler: Christian Richart. Ohio Dayton: Michael
Williams. North Ridgeville: John Schwab. Toledo: Mary C. Jensen. West Jefferson: Carolyn Loomis.
Pennsylvania Leesport: Lori Perchansky. Schuylkill Haven: Janet Steinmetz. Yardley: Peter
Stadelmeier. Rhode Island Rumford: Sarah A. Horst. South Dakota Piedmont: Randell Kenner.
Tennessee Clarksville: Kyle Hain. Knoxville: Nicole Hull. Texas Plano: Kristina Oberg. Virginia
Hampton: Edward Goodman. Herndon: Lisa Marsh-Vetter, Stephen M. Vetter. Washington Ferndale:
Candice Gerard. Millcreek: Nicki Taranto. Redmond: Andrea Frabotta. Wisconsin Beaver Dam:
Thomas Wendt. Mequon: Katie Molter ZIMBABWE Harare: Lesley Faye Marsh.
Answers (see pp. 7475 of the Spring 2005 issue for the questions): 1 (b), 2 (d), 3 (b), 4 (a), 5 (d), 6 (c), 7 (b), 8 (c), 9 (b), 10 (a),
11 (c), 12 (d), 13 (c), 14 (a), 15 (d), 16 (c), 17 (a), 18 (d), 19 (a), 20 (b), 21 (d), 22 (c), 23 (b), 24 (a), 25 (c)
CHALLENGE WINNERS
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279
GIA appreciates gifts to its permanent collection, as well as gemstones, library materials, and other non-cash assets
to be used in GIAs educational and research activities. These contributions help GIA further its public service
mission while offering donors significant philanthropic benefits. We extend sincere thanks to all 2004 contributors.
Joseph Rott
C.Y. Sheng
Alice and Lew Silverberg
Stone Flower Co. Russia
Under $500
Anonymous (8)
Allerton Cushman & Co.
(Tom Cushman)
Gilbert "Nono" Andrianairoson
Enrique Arizmende
Astorite Wholesalers
Astro Gallery of Gems
Stevan Borisavljevic
Murray Burford
Coleman Jewelers
Commercial Mineral Co., Inc.
Brian Cook
Thomas Currie
Makhmout Douman
J.C. Erasmus
Dana Gochenour
Stanley Goldklang
Dr. Tobias Hger
$1,000 to $2,499
David Hargreaves
Anonymous (5)
Frederick C. and Judith L. House
Pedro Boregaard
George Houston
Charles I. Carmona, G.G.
Jagoda Gems Ltd. (Zambia)
Eric Carstensen
Chris and Karen Johnston
Fine Cut Gems Co.
K. Girdharlal, Inc.
Fine Gems International
Terri J. Kafrissen
(Robert E. Kane)
Kaufman Enterprises
Si and Ann Frazier
Brendan M. Laurs
S. Gordon
Jack Lowell
Idaho Opal & Gem Corporation
Peter Lyckberg
Intimate Gems
Mary McNeil
(Farooq Hashmi)
Prof. Deric Metzger, G.J.G, A.J.P.
Feerie Jade
Rita Mittal
Kenneth F. Rose Gemstones
M.R. Lava Company
Alan Revere
Rene Newman
Sherri Gourley Skuble
The Nyman-Melnick Families
Wild & Petsch
Thomas W. Overton
Palcio Nacional Da Ajuda
$500 to $999
Federico Pezzotta
Anonymous (2)
Bob and Maria Pratsch
Accurate Appraisals
Premier Diamond
(Jaclynn K. Peterson)
Jose Vicente Rodriguez Rosa
Antique Cupboard
Dr. R. Shah
Carl S. Chilstrom
William George Shuster
Victoria duPont
Susan Eisen, Inc.
Mary Johnson and Mark Parisi
Suzanne's Source
Richard Knox
Tasaki Shinju Co., Ltd.
Joel Lackey, G.G.
Stephen Turner
Glen and Amanda Meyer
Dave Waisman
New Era Gems
Vladyslav Yavorskyy
Chen Zhonghui
Rev, Inc.
If you are interested in making a donation and receiving tax benefit information, please contact Patricia Syvrud at
(800) 421-7250, ext. 4432. From outside the U.S., call (760) 603-4432, fax (760) 603-4199. Or e-mail patricia.syvrud@gia.edu
Book REVIEWS
2005
Shinde Jewels
By Reema Keswani, 79 pp., illus.,
publ. by Assouline Publishing, New
York, 2004. US$18.95*
This is a spare, unassuming book that
clearly reflects a spare, unassuming
designer. A man of humble beginnings, Ambajii V. Shinde led a modest
lifestyle and sought only excellence in
his artan art that was a way of life
from the time he was a young boy
until his death in 2003 at the age of
85. Though he never strove for notoriety, he was sought out by Indian and
British royalty as well as by Hollywood glitterati. Harry Winston had
the vision to ask Shinde to join his
New York firm in 1959, then to head
the studio in 1966. What a marriage
of passion and art this was: A.V.
Shinde, the incomparable designer,
and Harry Winston, the man with the
cornucopia of gemstones.
A. V. Shinde was responsible for
designing some of the most magnificent jewels of the 20th century,
including the settings for the Star of
Sierra Leone, toile du Dsert, TaylorBurton, Star of Independence, and
Garuda diamonds. Yet he remained
largely unknown outside the world of
haute couture jewelry. He did not
sign his work, only the renderings
the design was his signature. Though
these pieces displayed a profusion of
diamonds and gemstones, the symmetry, elegance, and stark minimalism started a revolution in design and
wearability.
The 49 pages of lavish color photographs and renderings, unfettered
by captions, stand in silent testimony
to this quiet, elegant man. Here you
mainly see the object and the wearer,
BOOK REVIEWS
EDITORS
Susan B. Johnson
Jana E. Miyahira-Smith
Stuart Overlin
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282
BOOK REVIEWS
Totems to Turquoise:
Native North American
Jewelry Arts of the
Northwest and Southwest
Edited by Kari Chalker, Lois S.
Dubin, and Peter M. Whiteley, 224
pp., illus., publ. in association with
the American Museum of Natural
History by Harry N. Abrams, New
York, 2004. US$45.00*
In 2000, a cultural exchange program
brought Northwest Coastal Indian
artists to Arizona and New Mexico,
and Southwestern native artists to
British Columbia. The program introduced talented Haida, Navajo, and
Pueblo jewelers to one other and gave
them an opportunity to share their
cultures and arts. The exchange program eventually resulted in the
recently concluded Totems to
Turquoise exhibition at the American Museum of Natural History
(AMNH) in New York. Created as a
companion to the exhibit, this book
focuses on 39 contemporary North
American native artists, their work,
and their thoughts on individual roles
and responsibilities in supporting
their cultures and communities.
This high-quality 9.25 11.25 in.
book is divided into two main sections, The Northwest Coast and
The Southwest, and includes 150
full-color pages, two maps, and
numerous historical photos. Introductory chapters discuss each regions
landscape, culture, and history, followed by biographies of earlier master
jewelers such as Charles Edenshaw,
Bill Reid, Kenneth Begay, Preston
Monongye, and Charles Loloma.
Sections on contemporary artists follow those of the master craftsmen.
Noted photographer Kiyoshi Togashi
took the majority of the photos,
including images of the artists that
accompany their personal statements
and examples of their art.
An intimate portrait of each artist
emerges. The personal statements in
each section collectively create a larger impression of the group they represent. The totality of both sections
gives an even deeper understanding of
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BOOK REVIEWS
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283
Gemological ABSTRACTS
2005
EDITOR
A. A. Levinson
University of Calgary
Calgary, Alberta, Canada
REVIEW BOARD
Christopher M. Breeding
GIA Laboratory, Carlsbad
Maha Calderon
Carlsbad, California
Jo Ellen Cole
Vista, California
Eric Fritz
GIA Laboratory, Carlsbad
R. A. Howie
Royal Holloway, University of London
Alethea Inns
GIA Laboratory, Carlsbad
David M. Kondo
GIA Laboratory, New York
Taijin Lu
GIA Research, Carlsbad
Wendi M. Mayerson
GIA Laboratory, New York
Kyaw Soe Moe
GIA Laboratory, New York
Keith A. Mychaluk
Calgary, Alberta, Canada
Joshua Sheby
GIA Laboratory, New York
James E. Shigley
GIA Research, Carlsbad
Boris M. Shmakin
Russian Academy of Sciences, Irkutsk, Russia
Russell Shor
GIA, Carlsbad
Rolf Tatje
Duisburg University, Germany
Sharon Wakefield
Northwest Gem Lab, Boise, Idaho
GEMOLOGICAL ABSTRACTS
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DIAMONDS
Angola: Diamond production on the rise. N. Ford, African
Business, No. 309, 2005, pp. 5455.
With the end of Angolas civil war, the countrys stateowned diamond administration agency, Endiama, is
assuming a wider role in economic growth. Endiama
expects the countrys yearly diamond production to nearly
double by 2007, to 12 million carats from the 6.5 million
carats mined in 2004. With the increased yield, revenues
would be an estimated $2.2 billion. Part of this increase
will come from new production from both alluvial and
kimberlite mines. However, illegal mining and smuggling
of diamonds is still costing the Angolan government an
estimated $375 million yearly. The government is
attempting to crack down on the 250,000 illegal miners
who are responsible for this production.
RS
Colour in diamondyellow. J. Chapman, Rough
Diamond Review, Part I. No. 7, 2004, pp. 4244.
Diamond colour origins. Part II. No. 8, 2005, pp.
2326.
The origin of color in diamonds is an important research
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Interpreting diamond morphology. V. Afanasiev, N. Zinchuk, V. Sonin, and E. Semenets, Rough Diamond
Review, Part I. No. 5, 2004, pp. 3033; Part II. No.
7, 2004, pp. 2627.
Typomorphism is the ability of a mineral to reflect its formation conditions by means of its structural, morphological, and/or chemical characteristics. Russian mineralogists
have found that such characteristics (e.g., unique morphological and surface features) are of great value in interpreting the original growth, post-growth, and emplacement
conditions of diamonds, and for diamond prospecting on
the Siberian platform.
Although the primary habit of diamond is the octahedron, modifications to this shape are both common and
significant. After growth, the morphology of diamonds
may be modified while residing in the medium that
formed them and/or during the processes that eventually
brought them to the surface. Accordingly, two types of
post-growth alteration are recognized: dry (anhydrous,
without H2O) and wet (hydrous, with H2O). Dry morphogenesis is characterized by the rounding of growth layers, the development of parallel striations near octahedral
edges, and the formation of inverted trigons. These characteristics reflect post-growth activity in the host medium before entering the transport melt. Wet morphogenesis is characterized by the rounding of octahedral edges
leading to dodecahedral (dissolution) forms and occurs
within the transport melt.
Post-magmatic conditions, of which mechanical wear
during the formation of alluvial deposits is the most
important, can also lead to distinctive morphologies.
Although mechanical wear only slightly alters morphology, this process is very important from a typomorphic perspective. Mechanical wear is seen in two main forms,
striated surfaces and icicle features, both of which
result from mechanical polishing and abrasion of crystals
mainly at their edges and corners. Striated surfaces appear
as regular patterns of pitting or wear, whereas icicle features refer to smooth surfaces (with the appearance of ice)
that suggest such diamonds are very old and may have
been through numerous cycles of erosion and deposition.
Typomorphic features (including those obtained by
infrared spectroscopy and trace-element analysis) offer the
potential for determining the exact mine from which a
diamond originated.
DMK
The roles of primary kimberlitic and secondary Dwyka
glacial sources in the development of alluvial and
marine diamond deposits in southern Africa. J. M.
Moore [j.moore@ru.ac.za] and A. E. Moore, Journal
of African Earth Sciences, Vol. 38, No. 2, 2004, pp.
115134.
It is well known that the source of most of the alluvial
diamonds in southern Africa is a number of Cretaceous
(14565 million years [My]) kimberlites that have been
deeply eroded. Diamonds liberated from these kimberlites
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287
and high-temperature annealing. EPR (electron paramagnetic resonance) spectroscopy revealed some nitrogenrelated peaks and some transition-metal elements (mainly
Ni) related to fine structures in both the natural and the
synthetic diamonds. The Argyle sample showed two Nirelated peaks centered at 785 and 872 nm, as well as
seven unrecognized peaks that may be assigned to a Ni-N
complex.
TL
Three historical asteriated hydrogen-rich diamonds:
Growth history and sector-dependent impurity
incorporation. B. Rondeau [rondeau@mnhn.fr], E.
Fritsch, M. Guiraud, J.-P. Chalain, and F. Notari,
Diamond and Related Materials, Vol. 13, No. 9,
2004, pp. 16581673.
Three diamond cleavage plates (~0.130.15 ct), each
exhibiting symmetrical lobe- or petal-like color zones, were
investigated to gain a better understanding of their growth
structure and history. These historic type Ia diamonds, catalogued as part of the collection of the National Museum
of Natural History in Paris between sometime before 1822
and 1844, were studied by the famous 19th century French
mineralogists Ren-Just Hay and Alfred Descloizeaux. For
the present study, the samples were reexamined by spectroscopic, imaging, and luminescence techniques. Two of the
samples displayed either gray or brown lobe-shaped sectors
forming a three-fold arrangement in a near-colorless or light
brown matrix, while the third exhibited dark brown lobes
in a six-fold pattern in a light brown matrix. Each diamond
is an example of contemporaneous growth of both cuboid
(lobes) and octahedral (matrix) sectors, but with different
amounts of nitrogen and hydrogen.
The various shapes of the lobed patterns in the three
samples reflect a continuous variation in the relative
growth rates of the two kinds of sectors. The UV-Vis spectra of all three samples displayed increasing absorption
toward the UV region, which explains the gray or brown
color. One sample also displayed a 415 nm band (the N3
center) in the octahedral sector and numerous weak
absorption bands between 350 and 570 nm (due to H) in
the cuboid sector. IR spectra revealed enriched H and N
concentrations in both sectors, but H was greater in the
cuboid sectors (where it inhibited nitrogen aggregation),
whereas N was greater in the octahedral sectors.
Additional details of the IR and Raman spectra are presented, along with a discussion of the stages of incorporation of
N and H during diamond formation. Hydrogen appeared to
be incorporated in several different structural sites.
JES
GEM LOCALITIES
Cultured pearl resources and markets in China. H. Zhang
and B. Zhang, Journal of Gems and Gemmology,
Vol. 6, No. 4, 2004, pp. 1418 [in Chinese with
English abstract].
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two crystals gave 830 and 1444 ppm V, and only 8 and 14
ppm Cr). A CO2-bearing aqueous brine is present within
multiphase fluid inclusions along healed fractures in the
emerald. Emerald formation is estimated to have occurred
at pressures up to 320 MPa and temperatures between
200 and 610C. Preliminary stable isotope data indicate
that the emerald is derived from a magmatic source. The
Cretaceous granitic rocks are believed to be the source of
Be, while V was extracted from the shales. This deposit
has some geologic characteristics and conditions of formation similar to those at the Tsa Da Glisza (or Regal
Ridge) emerald occurrence in the Yukon.
JES
GEMOLOGICAL ABSTRACTS
Migration of the Mendocino Triple Junction and the origin of titanium-rich mineral suites at New Idria,
California. M. R. Van Baalen [mvb@harvard.edu],
International Geology Review, Vol. 46, No. 8, 2004,
pp. 671692.
The discovery of cinnabar ore in the New Idria District of
central California in 1851 began over a century of profitable
mercury mining. This, combined with the subsequent
exploration for oil in 1915, led to the discovery of several
useful minerals including magnesite, chromite, various
gems, and chrysotile (asbestos). Data on the formation and
composition of Ti-rich mineral suites associated with the
New Idria serpentinite are presented along with a new
petrologic model for their formation. These peculiar minerals, which include Ti-rich andradite garnets and benitoite,
underwent blueschist and lower greenschist metamorphism
associated with the tectonic passage of the Mendocino
Triple Junction and emplacement of the serpentinite ~12
million years ago. Previous workers had suggested that fluid
migration introduced several of the elements necessary for
the formation of the unusual mineral suites. However, more
recent studies have shown that the solubilities of these elements (e.g., Ti, Al, and Zr) are extremely low and would
require fluid transport over long distances.
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ultrabasites at about 500C and 2 kbar. F- and Be-rich fluids responsible for the emerald crystallization probably
originated from granites and granitic pegmatites that were
emplaced during the formation of the Ifanadiana-Angavo
shear zone roughly 550500 million years ago. Thermodynamic modeling explains the role of fluoride complexes
in the transport of Be. The solubility of Be increases as the
amount of F in aqueous solution increases. At the point of
crystallization of an F-rich mineral (F-phlogopite in this
case), the associated Be becomes unstable in solution and
begins to crystallize minerals that are able to incorporate it
into their structure (beryl in this case). Sufficient Cr within the ultrabasites enabled the formation of emerald.
EF
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TREATMENTS
Meaning of ions diffusion coefficient in sapphire diffusion
heat treatment. R. Yang, D. Yu, and J. Zhao, Journal
of Tongji University (Natural Science), Vol. 32, No.
9, 2004, pp. 11451148 [in Chinese with English
abstract].
Blue color enhancement of sapphire by surface-diffusion
processes at high temperatures has been reported since the
1980s. However, most treatment processes are based on
trial and error. In this article, the diffusion coefficients
of Fe and Ti ions in sapphire crystals calculated during various treatment conditions are presented. Colorless and
light blue sapphires were treated with (unspecified) Fe- and
Ti-containing chemicals in an aluminum oxide crucible at
a temperature of 1,8001,900C for up to 72 hours at a
Thai jewelry company. The thickness of the diffusion
layer was measured from samples cut into 0.8 mm thick
plates. The concentrations of Fe and Ti in different layers,
starting from the outer surface of the samples, were determined by electron-microprobe analysis.
The diffusion coefficients of Fe and Ti in sapphire are
mainly controlled by temperature, duration of the treatment, thickness of the diffused layer, and the initial concentrations of Fe2+ and Ti4+ ions in the chemical additives.
However, at certain temperatures, the diffusion coefficients of Fe and Ti ions were essentially constant, regardless of variations in the duration. The diffusion coefficient
of Ti ions was much greater than that of Fe ions, being
6.57 10 -9 cm2 . s -1 and 1.62 10 -9 cm2. s-1, respectively.
Using these coefficients in conjunction with specified
temperatures and duration times, it is possible to control
the thickness of the diffusion layer in sapphire. These
coefficients may also be useful toward lightening dark
colored sapphires, such as those from Shangdong, China.
TL
A treatment study of Brazilian garnets. S. G. Eeckhout, A.
C. S. Sabioni, and A. C. M. Ferreira, Journal of
Gemmology, Vol. 29, No. 4, 2004, pp. 205214.
Reports of gem treatments are widespread in the literature
but very few have been published on garnets. This article
reports on the enhancement of several types of mostly
gem-quality Brazilian garnets (pyrope, almandine-pyrope,
almandine-spessartine, and grossular), primarily from pegmatite and alluvial occurrences in the states of Minas
Gerais and Rio Grande do Norte. The authors determined
the enhancement response of these garnets to heat treatment in air, and in oxidizing (oxygen saturated), inert
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(argon saturated), and reducing (hydrogen saturated) atmospheres, at various temperatures (6001000C) and durations (generally 424 hours). The response of pale yellow
grossular to diffusion treatment (900C for 44 hours) using
oxides of Fe, Cr, and Co also was investigated.
Following heat treatment in both the oxidizing and
inert atmospheres, almandine-spessartine and pyrope
(containing 9.12 wt.% FeO) became opaque and were
coated with a silvery skin, caused by the formation of
hematite. The higher the iron content of the stone, the
more noticeable the silvery luster. The iron-rich (i.e.,
almandine-containing) stones became opaque and had a
burned, charcoal-like appearance after heating in air at
1,000C for 4 hours or 900C for 24 hours. Grossular samples turned orange after heating. No changes were
observed in any sample heated in the reducing environment at 800C for 4 hours.
Diffusion of Fe and Cr produced an orange layer on the
grossular samples, whereas diffusion of Co produced a
green layer. In general, longer treatment times and higher
temperatures resulted in a greater thickness of the diffused color.
WMM
MISCELLANEOUS
Comments on Canadas national diamond strategy. R.
Taplin [rtaplin@mccarty.ca] and T. Isaac, Journal of
Energy & Natural Resources Law, Vol. 22, No. 4,
2004, pp. 429449.
Canada has become one of the worlds primary diamond
producers, which has prompted the federal and several
provincial governments to draw up strategies that will (1)
maximize benefits for Canadians; (2) develop cooperation
between various governments, mining companies, and
local populations; and (3) encourage investment and development in all sectors of the industry.
The primary policy dilemma facing Canadas industry
is developing local diamond-manufacturing operations.
The governments want to increase employment and local
participation in the diamond industry, but mining companies claim that enforced supply to these operations results
in diminished profits. The companies also claim that this
deters future exploration and development. The current
national policy is to make such supply agreements voluntary; however, the article cites an example of strong pressure from the government of the Northwest Territories to
get BHP Billiton to offer 10% of its production from the
Ekati mine to local operations. More stringent requirements could run afoul of the North American Free Trade
Agreement and various other treaties and regulations.
The diamond industry and government also disagree
over Canadian Diamond branding efforts. The government believes that a Canadian diamond origin could carry
a premium in the market, while many in the industry do
not. This has led to a debate over whether diamonds
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The author reports that there remains little meaningful employment in the two provinces, and most people
still live by subsistence farming. Police and army officials
extort funds, not just from diamond diggers, but also from
health workers and traders. As a result, many of the
provinces inhabitants remain little better off than they
were before and during the civil war.
RS
Tackling conflict diamonds: The Kimberley Process Certification Scheme. C. Wright, International Peacekeeping, Vol. 11, No. 4, 2004, pp. 697708.
The Kimberley Process Certification Scheme for rough diamonds is the first attempt by the international community
to control illegal exploitation of natural resources. It is also
the first agreement adopted with an equal partnership
between governments, industry, and civil society groups.
The Kimberley Process (KP) was ratified by 54 governments, representatives of the diamond industry, and civil
society groups in November 2002. It was put into effect in
February 2003. Since then, several challenges to the process have arisen. In July 2003, 18 participating nations
were asked to leave until they had adopted proper legislation and internal controls to meet the minimum standards
for implementation. Six of these nations have subsequently rejoined. And, in early 2004, discrepancies between official diamond production in the Republic of the Congo and
the actual diamond exports coming from that nation
caused the KP chairman to withdraw its certification.
The Kimberley Process will receive a full review in
2006. Although the original reason for its adoptionto
stop the trade in conflict diamondsis less relevant
because the civil wars have ended, there is an argument
for retaining the system because of the potential for terrorists and criminals to launder or transport funds by diamond sales through illicit channels.
RS
Traditional gemstone cutting technology of Kongu region
of Tamil Nadu. K. Rajan and N. Athiyaman, Indian
Journal of History of Science, Vol. 39, No. 4, 2004,
pp. 385414.
The authors trace the long history of gem extraction and
cutting in Indias southern province of Tamil Nadu. The
Kongu region was, and remains, the source for many gem
varieties including beryl, corundum, quartz, and feldspar.
Accounts of artisans working gems in the area date back
to the 3rd century BC, and Pliny, in the 1st century AD,
noted that the best beryls, of a sea-green color, mostly
came from India.
The authors then discuss the villages of the region and
describe in detail the techniques and equipment still
employed today by traditional cutters in fashioning
faceted stones and beads in those areas.
RS
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