Smoky or smokey quartz is a brown to black variety of quartz

Quartz

Quartz is the second-most-abundant mineral in the Earth's continental crust, after feldspar. It is made up of a continuous framework of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall formula SiO2. There are many different varieties of quartz,...

. Like other quartz gems, it is a silicon dioxide

Silicon dioxide

The chemical compound silicon dioxide, also known as silica , is an oxide of silicon with the chemical formula '. It has been known for its hardness since antiquity...

 crystal. The smoky colour results from free silicon, formed from the silicon dioxide by natural irradiation.

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

Pliny the Elder

Gaius Plinius Secundus , better known as Pliny the Elder, was a Roman author, naturalist, and natural philosopher, as well as naval and army commander of the early Roman Empire, and personal friend of the emperor Vespasian...

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Cairngorm

Cairngorm is a variety of smoky quartz crystal

Crystal

A crystal or crystalline solid is a solid material whose constituent atoms, molecules, or ions are arranged in an orderly repeating pattern extending in all three spatial dimensions. The scientific study of crystals and crystal formation is known as crystallography...

 found in the Cairngorm Mountains of Scotland

Scotland

Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...

. It usually has a smokey yellow-brown colour, though some specimens are a grey-brown.

It is used in Scottish jewellery

Jewellery

Jewellery or jewelry is a form of personal adornment, such as brooches, rings, necklaces, earrings, and bracelets.With some exceptions, such as medical alert bracelets or military dog tags, jewellery normally differs from other items of personal adornment in that it has no other purpose than to...

 and as a decoration on kilt

Kilt

The kilt is a knee-length garment with pleats at the rear, originating in the traditional dress of men and boys in the Scottish Highlands of the 16th century. Since the 19th century it has become associated with the wider culture of Scotland in general, or with Celtic heritage even more broadly...

 pins and the handles of sgian dubh

Sgian Dubh

The sgian-dubh is a small, singled-edged knife worn as part of traditional Scottish Highland dress along with the kilt. It is worn tucked into the top of the kilt hose with only the upper portion of the hilt visible...

s (anglicised: skean dhu). The largest known cairngorm crystal is a 23.6 kg

Kilogram

The kilogram or kilogramme , also known as the kilo, is the base unit of mass in the International System of Units and is defined as being equal to the mass of the International Prototype Kilogram , which is almost exactly equal to the mass of one liter of water...

 (52 pound

Pound (mass)

The pound or pound-mass is a unit of mass used in the Imperial, United States customary and other systems of measurement...

) specimen kept at Braemar Castle

Braemar Castle

Braemar Castle is situated near the village of Braemar in Aberdeenshire, Scotland. It is a possession of the chief of Clan Farquharson and is leased to a local charitable foundation. It is open to the public.-History:...

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External links

• Mineral Galleries - smoky quartz