Tellurium is a chemical element; it has symbol Te and atomic number 52. It is a brittle, mildly toxic, rare, silver-white metalloid. Tellurium is chemically related to selenium and sulfur, all three of which are chalcogens. It is occasionally found in its native form as elemental crystals. Tellurium is far more common in the Universe as a whole than on Earth. Its extreme rarity in the Earth's crust, comparable to that of platinum, is due partly to its formation of a volatile hydride that caused tellurium to be lost to space as a gas during the hot nebular formation of Earth.
The mineral petzite, Ag3AuTe2, is a soft, steel-gray telluride mineral generally deposited by hydrothermal activity. It forms isometric crystals, and is usually associated with rare tellurium and gold minerals, often with silver, mercury, and copper.
Calaverite, or gold telluride, is an uncommon telluride of gold, a metallic mineral with the chemical formula AuTe2, with approximately 3% of the gold replaced by silver. It was first discovered in Calaveras County, California in 1861, and was named for the county in 1868.
The telluride ion is the anion Te2− and its derivatives. It is analogous to the other chalcogenide anions, the lighter O2−, S2−, and Se2−, and the heavier Po2−.
Krennerite is an orthorhombic gold telluride mineral which can contain variable amounts of silver in the structure. The formula is AuTe2, but specimen with gold substituted by up to 24% with silver have been found ([Au0.77Ag0.24]Te2). Both of the chemically similar gold-silver tellurides, calaverite and sylvanite, are in the monoclinic crystal system, whereas krennerite is orthorhombic.
Rickardite is a telluride mineral, a copper telluride (Cu7Te5) or Cu3-x (x = 0 to 0.36)Te2. It was first described for an occurrence in the Good Hope Mine, Vulcan district, Gunnison County, Colorado, US, and named for mining engineer Thomas Arthur Rickard (1864–1953). It is a low temperature hydrothermal mineral that occurs associated with vulcanite, native tellurium, cameronite, petzite, sylvanite, berthierite, pyrite, arsenopyrite and bornite.
Weissite is a telluride mineral, a copper telluride. Its chemical formula is Cu
2−xTe. Weissite has hexagonal crystal structure. Its specific gravity is 6 and its Mohs hardness is 3. Occurrence is in Gunnison County, Colorado, Arizona and New Mexico in the United States. It is also reported from Kalgoorlie, Western Australia and Dalarna and Värmland, Sweden.
Tellurobismuthite, or tellurbismuth, is a telluride mineral: bismuth telluride (Bi2Te3). It crystallizes in the trigonal system. There are natural cleavage planes in the (0001) direction as the crystal is effectively lamellar (layered) in that plane. The Mohs hardness is 1.5 – 2 and the specific gravity is 7.815. It is a dull grey color, which exhibits a splendent luster on fresh cleavage planes.
A native metal is any metal that is found pure in its metallic form in nature. Metals that can be found as native deposits singly or in alloys include antimony, arsenic, bismuth, cadmium, chromium, cobalt, indium, iron, manganese, molybdenum, nickel, niobium, rhenium, tantalum, tellurium, tin, titanium, tungsten, vanadium, and zinc, as well as the gold group and the platinum group. Among the alloys found in native state have been brass, bronze, pewter, German silver, osmiridium, electrum, white gold, silver-mercury amalgam, and gold-mercury amalgam.
Nagyágite is a rare sulfide mineral with known occurrence associated with gold ores. Nagyágite crystals are opaque, monoclinic and dark grey to black coloured.
Vulcanite is a rare copper telluride mineral. The mineral has a metallic luster, and has a green or bronze-yellow tint. It has a hardness between 1 and 2 on the Mohs scale. Its crystal structure is orthorhombic.
Gold chalcogenides are compounds formed between gold and one of the chalcogens, elements from group 16 of the periodic table: oxygen, sulfur, selenium, or tellurium.
Coloradoite, also known as mercury telluride (HgTe), is a rare telluride ore associated with metallic deposit. Gold usually occurs within tellurides, such as coloradoite, as a high-finess native metal.
Zemannite is a very rare oxide mineral with the chemical formula Mg0.5ZnFe3+[TeO3]3·4.5H2O. It crystallizes in the hexagonal crystal system and forms small prismatic brown crystals. Because of the rarity and small crystal size, zemannite has no applications and serves as a collector's item.
Stützite or stuetzite is a silver telluride mineral with formula: Ag5−xTe3 (with x = 0.24 to 0.36) or Ag7Te4.
Rodalquilarite is a rare iron tellurite chloride mineral with formula H3Fe3+2(Te4+O3)4Cl or Fe2(TeO2OH)3(TeO3)Cl. Rodalquilarite crystallizes in the triclinic system and typically occurs as stout green prisms and encrustations.
Telluro-silver glance — is a trivial name given by collectors and mineral dealers, miners, geologists and other professions to at least two ore mineralsrare ore minerals, tellurides of silver. It may refer to:
Telluric silver — is an obsolete trivial name, which collectors and mineral traders, miners, geologists and representatives of other applied professions actually applied to several rare ore minerals, tellurides of silver, as well as to chemical compounds of similar composition. It may refer to:
Marianna Sergeevna Bezsmertnaya, née Yurkevich was a Soviet and Russian geologist, mineralogist, petrographer and petrologist, candidate of geological and mineralogical sciences (1957), developer of new methods for diagnosing minerals, active participant and author of the discovery of a number of new minerals. For 25 years, he has been a leading employee of the Moscow Institute of Mineralogy, Geochemistry and Crystal Chemistry of Rare Elements, the author of new methods for determining minerals. In the late 1950s — early 1960s, she re-checked and revised the mineralogical collection of the institute.
Bezsmertnovite, less often bessmertnovite (Russian: Безсмертновит) is a very rare supergene mineral of the sulfide class, complex in composition: mixed plumbotelluride of gold, copper, iron, silver from the bilibinskite group with the calculation formula Au4Cu(Te,Pb).
