Search results
Results from the WOW.Com Content Network
Today this tourmaline locality (type locality for dravite) at Dobrova (near Dravograd), is a part of the Republic of Slovenia. [9] Tschermak gave this tourmaline the name dravite, for the Drava river area, which is the district along the Drava River (in German: Drau, in Latin: Drave) in Austria and Slovenia.
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 ...
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.
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]
In 2019, Brazil's figures were as follows: it was the world's largest producer of niobium (88.9 thousand tons); [2] the 2nd largest world producer of tantalum (430 tons); [3] the 2nd largest world producer of iron ore (405 million tons); [4] the 4th largest world producer of manganese (1.74 million tons); [5] the 4th largest world producer of bauxite (34 million tons); [6] the 4th largest ...
A large variety of minerals and gemstones are found in these mountains: emerald and tourmaline are found in the north, and garnet and quartz are found in the Bajaur and South Waziristan agencies. Department of Minerals is the government department working for the exploration and development of the mining industry in the region.
The second-largest mineral industry in the world is the mineral industry of Africa, which implies large quantities of resources due to Africa being the second largest continent, with 30.37 million square kilometres of land.With a population of 1.4 billion living there, mineral exploration and production constitute significant parts of their economies for many African countries and remain keys ...
The mineralogy of the gem deposits varies widely with, among others, corundum (sapphire, ruby), chrysoberyl, beryl, spinel, topaz, zircon, tourmaline, garnet being common. [2] Residual deposits are mainly found in flood plains of rivers and streams. The metamorphic types of gems constitute 90% of the gem deposits in Sri Lanka.