Bismite

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Bismite
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Bismite
General
Category Oxide minerals
Formula
(repeating unit)
Bi2O3
IMA symbol Bis [1]
Strunz classification 4.CB.60
Crystal system Monoclinic
Crystal class Prismatic (2/m)
(same H-M symbol)
Space group P21/c
Identification
ColorGrey
Fracture Uneven
Streak Grey to black
References [2]

Bismite is a bismuth oxide mineral, bismuth trioxide or Bi2O3. It is a monoclinic mineral, but the typical form of occurrence is massive and clay-like with no macroscopic crystals. The color varies from green to yellow. It has a Mohs hardness of 4 to 5 and a specific gravity of 8.5 to 9.5, quite high for a nonmetallic mineral.

Bismite is a secondary oxidation zone mineral which forms from primary bismuth minerals.

It was first described from Goldfield, Nevada in 1868, and later from the Schneeberg District, Ore Mountains, Saxony, Germany.

See also

Related Research Articles

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Antimony is a chemical element; it has symbol Sb (from Latin stibium) and atomic number 51. A lustrous gray metalloid, it is found in nature mainly as the sulfide mineral stibnite (Sb2S3). Antimony compounds have been known since ancient times and were powdered for use as medicine and cosmetics, often known by the Arabic name kohl. The earliest known description of the metalloid in the West was written in 1540 by Vannoccio Biringuccio.

<span class="mw-page-title-main">Pyrochlore</span> Niobium mineral of A2B2O7 general formula

Pyrochlore2Nb2O6(OH,F) is a mineral group of the niobium end member of the pyrochlore supergroup. Pyrochlore is also a term for the crystal structure Fd3m. The name is from the Greek πῦρ, fire, and χλωρός, green because it typically turns green on ignition in classic blowpipe analysis.

<span class="mw-page-title-main">Pnictogen</span> Group 15 elements of the periodic table with valency 5

A pnictogen is any of the chemical elements in group 15 of the periodic table. Group 15 is also known as the nitrogen group or nitrogen family. Group 15 consists of the elements nitrogen (N), phosphorus (P), arsenic (As), antimony (Sb), bismuth (Bi), and moscovium (Mc).

<span class="mw-page-title-main">Valentinite</span>

Valentinite is an antimony oxide mineral with formula Sb2O3. Valentinite crystallizes in the orthorhombic system and typically forms as radiating clusters of euhedral crystals or as fibrous masses. It is colorless to white with occasional shades or tints of yellow and red. It has a Mohs hardness of 2.5 to 3 and a specific gravity of 5.76. Valentinite occurs as a weathering product of stibnite and other antimony minerals. It is dimorphous with the isometric antimony oxide senarmontite.

A trioxide is a compound with three oxygen atoms. For metals with the M2O3 formula there are several common structures. Al2O3, Cr2O3, Fe2O3, and V2O3 adopt the corundum structure. Many rare earth oxides adopt the "A-type rare earth structure" which is hexagonal. Several others plus indium oxide adopt the "C-type rare earth structure", also called "bixbyite", which is cubic and related to the fluorite structure.

Molybdenum trioxide describes a family of inorganic compounds with the formula MoO3(H2O)n where n = 0, 1, 2. The anhydrous compound is produced on the largest scale of any molybdenum compound since it is the main intermediate produced when molybdenum ores are purified. The anhydrous oxide is a precursor to molybdenum metal, an important alloying agent. It is also an important industrial catalyst. It is a yellow solid, although impure samples can appear blue or green.

<span class="mw-page-title-main">Litharge</span>

Litharge (from Greek lithargyros, lithos 'stone' + argyros 'silver' λιθάργυρος) is one of the natural mineral forms of lead(II) oxide, PbO. Litharge is a secondary mineral which forms from the oxidation of galena ores. It forms as coatings and encrustations with internal tetragonal crystal structure. It is dimorphous with the yellow orthorhombic form massicot. It forms soft (Mohs hardness of 2), red, greasy-appearing crusts with a very high specific gravity of 9.14–9.35. PbO may be prepared by heating lead metal in air at approximately 600 °C (lead melts at only 300 °C). At this temperature it is also the end product of heating of other lead oxides in air. This is often done with a set of bellows pumping air over molten lead and causing the oxidized product to slip or fall off the top into a receptacle, where it quickly solidifies in minute scales.

<span class="mw-page-title-main">Arsenic trioxide</span> Chemical compound (industrial chemical and medication)

Arsenic trioxide is an inorganic compound with the formula As
2
O
3
. As an industrial chemical, its major uses include the manufacture of wood preservatives, pesticides, and glass. It is sold under the brand name Trisenox among others when used as a medication to treat a type of cancer known as acute promyelocytic leukemia. For this use it is given by injection into a vein.

<span class="mw-page-title-main">Antimony trioxide</span> Chemical compound

Antimony(III) oxide is the inorganic compound with the formula Sb2O3. It is the most important commercial compound of antimony. It is found in nature as the minerals valentinite and senarmontite. Like most polymeric oxides, Sb2O3 dissolves in aqueous solutions with hydrolysis. A mixed arsenic-antimony oxide occurs in nature as the very rare mineral stibioclaudetite.

<span class="mw-page-title-main">Bismuth(III) oxide</span> Chemical compound

Bismuth(III) oxide is a compound of bismuth, and a common starting point for bismuth chemistry. It is found naturally as the mineral bismite (monoclinic) and sphaerobismoite, but it is usually obtained as a by-product of the smelting of copper and lead ores. Dibismuth trioxide is commonly used to produce the "Dragon's eggs" effect in fireworks, as a replacement of red lead.

In chemistry, an arsenite is a chemical compound containing an arsenic oxyanion where arsenic has oxidation state +3. Note that in fields that commonly deal with groundwater chemistry, arsenite is used generically to identify soluble AsIII anions. IUPAC have recommended that arsenite compounds are to be named as arsenate(III), for example ortho-arsenite is called trioxidoarsenate(III). Ortho-arsenite contrasts to the corresponding anions of the lighter members of group 15, phosphite which has the structure HPO2−3 and nitrite, NO−2 which is bent.

<span class="mw-page-title-main">Bismutite</span> Bismuth carbonate mineral

Bismutite or bismuthite is a bismuth carbonate mineral with formula Bi2(CO3)O2 (bismuth subcarbonate). Bismutite occurs as an oxidation product of other bismuth minerals such as bismuthinite and native bismuth in hydrothermal veins and pegmatites. It crystallizes in the orthorhombic system and typically occurs as earthy to fibrous masses.

<span class="mw-page-title-main">Bismuth</span> Chemical element, symbol Bi and atomic number 83

Bismuth is a chemical element; it has symbol Bi and atomic number 83. It is a post-transition metal and one of the pnictogens, with chemical properties resembling its lighter group 15 siblings arsenic and antimony. Elemental bismuth occurs naturally, and its sulfide and oxide forms are important commercial ores. The free element is 86% as dense as lead. It is a brittle metal with a silvery-white color when freshly produced. Surface oxidation generally gives samples of the metal a somewhat rosy cast. Further oxidation under heat can give bismuth a vividly iridescent appearance due to thin-film interference. Bismuth is both the most diamagnetic element and one of the least thermally conductive metals known.

Mineral trioxide aggregate (MTA) is an alkaline, cementitious dental repair material. MTA is used for creating apical plugs during apexification, repairing root perforations during root canal therapy, and treating internal root resorption. It can be used for root-end filling material and as pulp capping material. It has better pulpotomy outcomes than calcium hydroxide or formocresol, and may be the best known material, as of 2018 data. For pulp capping, it has a success rate higher than calcium hydroxide, and indistinguishable from Biodentin.

<span class="mw-page-title-main">Bismoclite</span>

Bismoclite is a bismuth oxohalide mineral with formula BiOCl. It is the naturally occurring form of bismuth oxychloride. The name was derived from its chemical constituents. It is a secondary bismuth mineral first thought to be composed of bismuthyl ions (BiO+) and chloride anions, however, the existence of the diatomic bismuthyl ion is doubtful.

<span class="mw-page-title-main">Sodium bismuthate</span> Chemical compound

Sodium bismuthate is an inorganic compound, and a strong oxidiser with chemical formula NaBiO3. It is somewhat hygroscopic, but not soluble in cold water, which can be convenient since the reagent can be easily removed after the reaction. It is one of the few water insoluble sodium salts. Commercial samples may be a mixture of bismuth(V) oxide, sodium carbonate and sodium peroxide.

Daubréeite is a rare bismuth oxohalide mineral with formula BiO(OH,Cl). It is a creamy-white to yellow-brown, soft, earthy clay–like mineral which crystallizes in the tetragonal crystal system. It is a member of the matlockite group.

Tistarite is an exceedingly rare mineral with the formula Ti2O3, thus being the natural analogue of titanium(III) oxide. In terms of chemistry it is the titanium-analogue of hematite, corundum, eskolaite, and karelianite. Other minerals with the general formula A2O3 are arsenolite, avicennite, claudetite, bismite, bixbyite, kangite, sphaerobismoite, yttriaite-(Y) and valentinite. Tistarite and grossmanite – both found in the famous Allende meteorite (so is kangite) – are the only currently known minerals with trivalent titanium. Titanium in minerals is almost exclusively tetravalent. The only known terrestrial occurrence of tistarite was found during minerals exploration by Shefa Yamim Ltd. in the upper mantle beneath Mount Carmel, Israel.

Yttriaite-(Y) is an exceedingly rare mineral, a natural form of yttrium oxide, Y2O3. In terms of chemistry it is yttrium-analogue of kangite, arsenolite, avicennite and senarmontite (isometric minerals). Other minerals with the general formula A2O3 include corundum, bismite, bixbyite, eskolaite, hematite, karelianite, sphaerobismoite, tistarite, and valentinite. Yttriaite-(Y) forms tiny inclusions in native tungsten.

References

  1. Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi: 10.1180/mgm.2021.43 . S2CID   235729616.
  2. Mineralienatlas