Geograph - photograph every grid square

Easdale island lies in the Firth of Lorn directly opposite the village of Ellenabeich which is located at the southwestern tip of the Isle of Seil (Saoil).
It is one of a group of islands known as the Slate Islands due to their production of that commodity for many years.
Easdale is remarkable for several reasons; it has been quite dramatically excavated for slate giving it a rather moth-eaten appearance - much more so, as a percentage than any of the other Slate Islands with the possible exception of tiny Belnahua.
Despite its small size it has a thriving pub / restaurant, the 'Puffer Bar' - something many larger islands do not possess. Perhaps most remarkably it is the most densely populated of all Scottish islands with 235 people per km² - but this is a quirk of its tiny size as its total population is only about 60. This figure however is a remarkable increase on its lowest ebb when only five people remained on the island in the early 1960s.

Statistics for Easdale:
Area: 25ha (62 acres)
Population: 59
Density: 235/km² (609/mile²)
Highest point: (Unnamed) 38m (125')
Chief (and only) settlement: Easdale Village (100% of population)
Note the area of the island given above is at MHWS (Mean High Water Springs) i.e. land that is always (usually) above sea level. At low tide the island's area increases by almost precisely 50% to 37.6 ha (93 acres)

The whole of Easdale island is a conservation area - see map: Link
The former slate workings and quarries are a scheduled monument: Link
Almost every cottage is HES Cat 'C' listed - there are 22 separate listings:
No.1 Link - Note that this is the most informative listing
Nos.2-5 Link
Nos.8,100 & 6 Link
The Drill Hall Link
No.9 Link
Nos. 11,11A & 11B Link
Nos. 12 & 12A Link
No.13 Link
No.15 Link
Nos. 32,18 & 19 Link
No.29 Link
No.23 Link
No.24 Link
Nos.31,33A & 33 Link
Nos.34 & 35 Link
Nos. 41-43 Link
No.44 Link
No.48 Link
No.36 Link
The Coaley Link
No.55 Link
Nos.50-54 Link

Easdale's own website: Link
See also this Guardian article: Link

The group of islands known as The Slate Islands form an archipelago in the Firth of Lorn to the SSW of Oban.
They get their name from the fact that they were extensively quarried for slate, particularly in the C19th. The populations of these islands were then much higher than they are now, with most of the men involved in quarrying the slate.
There are four principal Slate Islands, Easdale, Seil, Luing and Belnahua. Some also include the islands of Torsa (113 ha (280 acres)) and Shuna (451 ha (1,114 acres)) though neither of these islands had slate commercially extracted. These two small islands lie off the eastern coast of Luing, and while Torsa does have slate formations which were never exploited, Shuna is mostly composed of other rocks. See the end of this article for information on yet more 'claimants' to Slate Island status!
The two smallest islands, Easdale and Belnahua were the most extensively quarried, at least as a percentage of their land area.
Belnahua, the smallest island at just 6ha (15 acres) is no longer inhabited and access to it requires organising a trip with a local boatman. At its most active however as many as 200 people lived on this tiny island.
For information on the main four Slate Islands, please see their own shared descriptions, listed below:
Belnahua: Link
Easdale (Eilean Eisdeal): Link
Seil (Saoil): Link
Luing (Luinn): Link

Various other islands and islets are occasionally included within the Slate Islands. Most of these would more accurately be called 'Islands of the Firth of Lorn' as they are included purely for their geographical location rather than any appreciable quarrying of slate (or any at all in many cases). The two largest islands sometimes referred to in this way are Kerrera (1,214 ha (4.69 miles²)) just off the coast from Oban and lofty Scarba (1,474 ha (5.69 miles²) which reaches an altitude of 449m (1,473')) which lies between Luing and Jura.
Some of the smaller islets that are sometimes considered to be Slate Islands are those that cluster to the west of Luing , namely (from roughly south to north)
Lunga (Lorn not Treshnish) (250 ha (1 mile²)),
Eilean Dubh Mor (50 ha (124 acres)) & Beag (15 ha (37 acres)),
Ormsa, Dubh Sgeir, Fladda and also, off the western coast of Seil the substantial Insh Island (33 ha (82 acres)).
I don't think that the Garvellachs were ever considered as Slate Islands however.