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The original Vantablack coating was grown from a chemical vapour deposition process (CVD) and is claimed to be the "world's darkest material" absorbing up to 99.965% of visible light measured perpendicular to the material. [6] [7] The coatings are unique in that they are super-black and retain uniform light absorption from almost all viewing ...
Taaffeite (/ ˈ t ɑː f aɪ t /; BeMgAl 4 O 8) is a mineral, named after its discoverer Richard Taaffe (1898–1967) who found the first sample, a cut and polished gem, in October 1945 in a jeweler's shop in Dublin, Ireland. [4] [5] As such, it is the only gemstone to have been initially identified from a faceted stone.
Riebeckite is a sodium-rich member of the amphibole group of silicate minerals, chemical formula Na 2 (Fe 2+ 3 Fe 3+ 2)Si 8 O 22 (OH) 2. It forms a solid solution series with magnesioriebeckite. It crystallizes in the monoclinic system, usually as long prismatic crystals showing a diamond-shaped cross section, but also in fibrous, bladed ...
Sodalite (/ ˈ s oʊ. d ə ˌ l aɪ t / SOH-də-lyte) is a tectosilicate mineral with the formula Na 8 (Al 6 Si 6 O 24)Cl 2, with royal blue varieties widely used as an ornamental gemstone. Although massive sodalite samples are opaque, crystals are usually transparent to translucent. Sodalite is a member of the sodalite group with hauyne ...
Classic peridotite is bright green with some specks of black, although most hand samples tend to be darker green. Peridotitic outcrops typically range from earthy bright yellow to dark green; this is because olivine is easily weathered to iddingsite. While green and yellow are the most common colors, peridotitic rocks may exhibit a wide range ...
Wolframite is an iron, manganese, and tungstate mineral with a chemical formula of (Fe,Mn)WO 4 that is the intermediate mineral between ferberite (Fe 2+ rich) and hübnerite (Mn 2+ rich). [4] Along with scheelite , the wolframite series are the most important tungsten ore minerals.
Emery, or corundite, is a dark granular rock used to make an abrasive powder. The rock largely consists of corundum (aluminium oxide), mixed with other minerals. Industrial emery may contain a variety of other minerals and synthetic compounds. Crushed or naturally eroded emery (known as black sand) is used as an abrasive. Turkey and Greece are ...
Rare "trapiche" emeralds are found in Colombia, distinguished by ray-like spokes of dark impurities. Zambia is the world's second biggest producer, with its Kafubu River area deposits (Kagem Mines) about 45 km (28 mi) southwest of Kitwe responsible for 20% of the world's production of gem-quality stones in 2004. [28]