Scotland has both gold, and coal, but neither have so far been discovered in Orkney, Shetland or the Outer Hebrides. However, a number of other precious stones, metals and minerals have been discovered or mined in the islands over the last 200 years.

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Copper was discovered in Sandwick on Shetland in 1789. In the following years this mine went on to be operated by various companies. It is thought to have been the most profitable mine in Shetland and had reached a depth of 84m by the time it closed in 1929. Other mines for iron, lead, zinc, chromium and magnetite were also opened, but most of these were less successful.

 

Although copper, iron, lead and even uranium have been found in Orkney, attempts to mine them have not brought much prosperity.

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The Outer Hebrides is the only one of the island groups in which precious stones have been found. In fact it is the only place in the UK where gem quality sapphires have been discovered.

 

 In 1994 a team of geologists found a 242 carat sapphire. This huge sapphire was later carved up into smaller 1 and 0.5 carat sapphires for use in jewellery, while a smaller one, now part of the collections of National Museums of Scotland, can be seen on display in Museum nan Eilean.