Search results
Results From The WOW.Com Content Network
Smoky quartz is a brownish grey, translucent variety of quartz that ranges in clarity from almost complete transparency to an almost-opaque brownish-gray or black crystals. [6] The color of smoky quartz is produced when natural radiation, emitted from the surrounding rock, activates color centers around aluminum impurities within the ...
The major collecting areas are on the west side of the mountain and they contain the usual assortment of smoky quartz and amazonite, although, like the Tarryalls, the amazonite is usually very pale and is most often grades into plain microcline. Devils Head is most noted for large topaz crystals and even larger smoky quartz crystals.
Spessartine on smoky quartz: Wushan Spessartine Mine, Tongbei, Fujian Province, China Reddish-orange spessartine Two "frog-eyes" of 1.8 cm each sit perched atop a matrix
Quartz is, therefore, classified structurally as a framework silicate mineral and compositionally as an oxide mineral. Quartz is the second most abundant mineral in Earth's continental crust, behind feldspar. [10] Quartz exists in two forms, the normal α-quartz and the high-temperature β-quartz, both of which are chiral. The transformation ...
In 1975, Telequartz Group, financed X-tal do Brasil factory producing oscillators and high quality optic fiber made by their own artificial quartz produced in laboratory. In 1988, Telequartz reached a joint venture with CVRD and Nisso Iwai Ltd. to build a U$20 million quartz powder plant in Minas Gerais, Brazil. The powder is an important ...
Smoky quartz is a brown to black variety of quartz. It goes by various names, depending on the colour: a dark-brown to black opaque variety is called "morion"; a yellow-brown variety from Scotland is known as "cairngorm", the colour being a result of ferric oxide impurity.
Jasper, an aggregate of microgranular quartz and/or cryptocrystalline chalcedony and other mineral phases, [1] [2] is an opaque, [3] impure variety of silica, usually red, yellow, brown or green in color; and rarely blue.
A rough specimen of bloodstone. Heliotropes (from Ancient Greek ἥλιος (hḗlios) 'sun' and τρέπειν (trépein) 'to turn') (also called ematille, Indian bloodstones, or simply bloodstones) are aggregate minerals, and cryptocrystalline mixture of quartz that occurs mostly as jasper or sometimes as chalcedony (translucent).