14 Photos
Smoky Quartz
Chemical Formula	SiO2
Species	Silicates
Crystal System	Trigonal
Mohs Scale	7
Specific Gravity	2.59-2.63
Color	gray, brown, black
Luster	Vitreous
Diaphaneity	Transparent, Translucent

Smoky or smokey quartz is a brown to black variety of quartz. Like other quartz gems, it is a silicon dioxide crystal. The smoky colour results from free silicon, formed from the silicon dioxide by natural irradiation.

Varieties

Morion

A very dark brown to black opaque variety is known as morion. Morion is the German, Danish, Spanish and Polish synonym for smoky quartz. The name is from a misreading of mormorion in Pliny the Elder.

Cairngorm

Cairngorm is a variety of smoky quartz crystal found in the Cairngorm Mountains of Scotland. It usually has a smokey yellow-brown colour, though some specimens are a grey-brown.

It is used in Scottish jewellery and as a decoration on kilt pins and the handles of sgian dubhs (anglicised: skean dhu). The largest known cairngorm crystal is a 23.6 kg (52 pound) specimen kept at Braemar Castle.

Uses

Sunglasses, in the form of flat panes of smoky quartz, were used in China in the 12th century.