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    Emerald Guide

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    celia m c corrigliano
    The quality and value of an emerald depends on its carat weight, shape and cut, colour, clarity, and transparency. Carat weight measures the stone's weight in grams, with higher carats being rarer and more valuable. Shape, cut, and polish also impact brilliance and how light moves through the stone. Colour comes from chromium and vanadium levels and varies between mines. Clarity relates to inclusions, and transparency refers to light transmission ability. Modifications like fissure filling can enhance clarity but must be disclosed.

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    Emerald Guide

    Uploaded by

    celia m c corrigliano
    109 views2 pages
    The quality and value of an emerald depends on its carat weight, shape and cut, colour, clarity, and transparency. Carat weight measures the stone's weight in grams, with higher carats being rarer and more valuable. Shape, cut, and polish also impact brilliance and how light moves through the stone. Colour comes from chromium and vanadium levels and varies between mines. Clarity relates to inclusions, and transparency refers to light transmission ability. Modifications like fissure filling can enhance clarity but must be disclosed.

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    The quality and value of an emerald depends on its carat weight, shape and cut, colour, clarity, and transparency. Carat weight measures the stone's weight in grams, with higher carats being rarer and more valuable. Shape, cut, and polish also impact brilliance and how light moves through the stone. Colour comes from chromium and vanadium levels and varies between mines. Clarity relates to inclusions, and transparency refers to light transmission ability. Modifications like fissure filling can enhance clarity but must be disclosed.

    Copyright:

    © All Rights Reserved
    Download as PDF, TXT or read online from Scribd
    Download as pdf or txt
    109 views2 pages

    Emerald Guide

    Uploaded by

    celia m c corrigliano
    The quality and value of an emerald depends on its carat weight, shape and cut, colour, clarity, and transparency. Carat weight measures the stone's weight in grams, with higher carats being rarer and more valuable. Shape, cut, and polish also impact brilliance and how light moves through the stone. Colour comes from chromium and vanadium levels and varies between mines. Clarity relates to inclusions, and transparency refers to light transmission ability. Modifications like fissure filling can enhance clarity but must be disclosed.

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    © All Rights Reserved
    Download as PDF, TXT or read online from Scribd
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    Emerald

    The quality and value of an emerald is dependant on a combination of the following criteria:

    An emerald’s weight is measured in carats. 5 carats = 1 gram. All other criteria being equal, the greater the
    carat weight, the rarer the emerald and therefore greater its value. Illustrated below is the approximate
    appearance of a well cut octagon shaped emerald for a given carat weight.

    CARAT

    SHAPE AND CUT

    To optimize the natural rough, emeralds are cut into a wide variety of shapes such as those illustrated below.

    CUT

    PROFILE

    Cut refers to the accuracy of the angles, proportions, symmetry


    and polish of the emerald. It greatly affects how light travels
    within the emerald, and how it exits in the form of brilliance.

    Colour is a matter of personal preference. Emeralds vary in colour depending mainly upon their chromium
    and vanadium content. Therefore emeralds from different countries* and mines have different predominant
    colours. Emeralds range from bluish and yellowish shades to brownish ones. But, a natural colour will always
    have a greater value than an equivalent colour obtained by any other process.

    COLOUR

    * Main countries where emeralds are mined: Afghanistan, Brazil, Columbia, India, Madagascar,
    Nigeria, Pakistan, Russia, South Africa, Tanzania, Zambia, Zimbabwe
    Inks and paper are subject to aging and differences in printing techniques. Therefore these colours should not be used for colour references.

    The clarity of an emerald is determined by the number, size and location of inclusions which
    are present in the stone. They reflect its fascinating geological aspects. Internally and
    INCLUSIONS externally too, there may be the presence of fissures, fractures and cavities which affect
    clarity.
    Eye Clean Slightly Included Included

    CLARITY

    Transparency refers to the ability of an emerald to transmit light. It is affected by the


    TRANSPARENCY
    quantity or absence of opacity and brilliance present in the stone.

    Transparent Translucent Opaque

    FOR MORE INFORMATION REGARDING EMERALD MODIFICATIONS, SYNTHETICS AND IMITATIONS REFER TO THE BACK.
    Gemstone Modification

    A NATURAL UNPROCESSED EMERALD IS VERY RARE; IT HAS A GREATER INTRINSIC VALUE


    THAN ONE WHICH HAS UNDERGONE ANY OF THE FOLLOWING MAIN PROCESSES:

    CLARITY MODIFICATION: Besides cutting and polishing, emeralds are commonly modified to
    improve their colour and clarity.

    FISSURE FILLING: Fissures, wide fractures and cavities may be filled with colourless and/or near-
    colourless oil, resins or other agents to significantly improve clarity.

    DYED: Beryl / Emeralds may undergo a substantial colour modification through the filling of fissures
    and fractures with coloured agents.

    It is required that customers be informed about such modifications.


    Ask for a written confirmation.

    Value of a gemstone
    In addition to the information on the front, the value of a gemstone is also defined by the
    combination of relative beauty, rarity and durability.

    Synthetic and imitation stones can be produced in industrial plants in any quantity and are
    therefore not rare and not considered precious. As a result, they cost much less than their natural
    counterparts of equal characteristics.

    For additional information and knowledge, please refer to the CIBJO Gemstone Book available at:

    The World Jewellery Confederation (CIBJO)


    Piazzale Carlo Magno, 1
    20149 Milano, Italy

    Phone: +39 02 4997 7098 / 7097


    Fax: +39 02 4997 7059
    E-Mail: cibjo@cibjo.org
    Website: www.cibjo.org

    All rights reserved. No part of this Guide may be reproduced, republished, amended, translated or
    changed without the express written permission of CIBJO or its authorized agents. Permission to republish,
    reproduce and/or translate of this Guide is limited to CIBJO member organizations only, and is subject to written
    agreements between CIBJO and/or its agents and the CIBJO membership organization.

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