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Gem and specimen tourmaline is mined chiefly in Brazil and many parts of Africa, including Tanzania, Nigeria, Kenya, Madagascar, Mozambique, Malawi, and Namibia. It is also mined in Asia, notably in Pakistan, Afghanistan, and Indonesia as well as in Sri Lanka and India, [25] where some placer material suitable for gem use is found.
Amethyst crystals – a purple quartz Apophyllite crystals sitting right beside a cluster of peachy bowtie stilbite Aquamarine variety of beryl with tourmaline on orthoclase Arsenopyrite from Hidalgo del Parral, Chihuahua, Mexico Aurichalcite needles spraying out within a protected pocket lined by bladed calcite crystals Austinite from the Ojuela Mine, Mapimí, Durango, Mexico Ametrine ...
Rubellite is the red or pink variety of tourmaline and is a member of elbaite. Rubellite is also the rarest gem in its family. [2] It is occasionally mistaken for ruby. [3] These gems typically contain inclusions. [4] Notable countries where rubellite can be mined include Afghanistan, Brazil, Madagascar, Myanmar, Nigeria, Russia, and the United ...
Examples include aquamarine, tourmaline, topaz, fluorite, apatite, and corundum, often along with tin, rare earth, and tungsten minerals, among others. [17] [3] Pegmatites have been mined for both quartz and feldspar. [26] For quartz mining, pegmatites with central quartz masses have been of particular interest. [26]
Staurolite is a common metamorphic intermediate-grade index mineral. It has a particularly complicated crystal structure that was only fully described in 1986. Topaz (Al 2 SiO 4 (F, OH) 2, often found in granitic pegmatites associated with tourmaline, is a common gemstone mineral. [132]
Elbaite, a sodium, lithium, aluminium boro-silicate, with the chemical composition Na(Li 1.5 Al 1.5)Al 6 Si 6 O 18 (BO 3) 3 (OH) 4, [4] is a mineral species belonging to the six-member ring cyclosilicate tourmaline group. Elbaite forms three series, with dravite, with fluor-liddicoatite, and with schorl.
Gemstones have been found in Greenland, including diamond, ruby, sapphire, kornerupine, tugtupite, lapis lazuli, amazonite, peridot, quartz, spinel, topaz, and tourmaline. [1] Most of Greenland's ruby and sapphire occurrences are located near the village of Fiskenaesset/ Qeqertarsuatsiaat on the southwest coast.
The extracts from Rubislaw Quarry are described as being 'blue granite' or 'grey granite', as opposed to the 'red granite' found in quarries near Peterhead, Scotland. The colour depends on the hue of quartz and feldspar and its ratio with mica. Matthew Forster Heddle found the quarry a good source of the minerals tourmaline and beryl.