Cairngorms

[SherbrookeJacobite]

Thanks Pol - its always nice to learn something new.

[pogofish]

A bit more info from here:

http://en.wikipedia.org/wiki/Cairngorm

Cairngorm is a variety of quartz crystal originally found in the Cairngorm Mountains of Scotland. It usually has a smokey yellow-brown colour, though some specimens are a grey-brown. Like other quartz gems, it is a silicon dioxide crystal, with a small amount of ferric oxide impurity which gives it the characteristic colour. It is used in Scottish jewellery and as a decoration on kilt pins and the handles of sgian dubhs (more widely known by the anglicised version skean dhu). The largest known cairngorm crystal is a 52-pound (23.6-kilogram) specimen kept at Braemar Castle.

More on Scots minerals here:

http://www.curriehj.freeserve.co.uk/typeloc.htm