stibnite

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A mineral with composition Sb₂S₃ (antimony trisulfide), the chief ore of antimony. It crystallizes in slender, prismatic, vertically striated crystals which may be curved or bent. It is often in bladed, granular, or massive aggregates. The hardness is 2 on Mohs scale and the specific gravity 4.5–4.6. The luster is metallic and the color lead-gray to black. It is one of few minerals that fuses easily in the match flame (525°C or 977°F).

Stibnite has been found in various mining districts in Germany, Romania, France, Bolivia, Peru, and Mexico. In the United States the Yellow Pine mine at Stibnite, Idaho, is the largest producer. Other deposits are in Nevada and California. The finest crystals have come from the island of Shikoku, Japan. See also Antimony.

Stibnite is a lead-gray mineral (Sb₂S₃) with a metallic luster. It is the most important ore of antimony, and is also known as antimony glance. One of the few minerals that fuse easily in a match flame (977°F or 525°C), stibnite has a hardness of two on the Mohs scale and a specific gravity of 4.5 to 4.6. It is commonly found in hydrothermal veins or hot springs deposits. Stibnite is mined in Germany, Romania, France, Bolivia, Peru, and Mexico. The Yellow Pine mine at Stibnite, Idaho, is the largest producer in the United States, but California and Nevada also have deposits.

Environment

In low-temperature, often open, veins and rock impregnations. Associated with arsenic and antimony minerals.

Usually in well-formed crystals, sometimes very large and solid (Japan, China); at other times stocky and short, slender and fragile, or fibrous, massive, bladed, or granular.

Steel gray. Luster metallic; hardness 2; specific gravity 4.5-4.6; streak black; fracture subconchoidal; cleavage perfect side pinacoid.

Sulfide of antimony (71.7% Sb, 28.3% S).

Melts to a liquid, spreads out and completely volatilizes on charcoal, making a white coating around grain and weakly coloring the blowpipe flame white. Dissolves in hot concentrated HNO ₃ and slowly forms a white precipitate on addition of water.

Distinguished from lead-bearing sulfosalts by the lack of a yellow (lead oxide) coating on the surrounding charcoal and by its complete volatility. Distinguished from bismuthinite by lower gravity, more fluid fusion on charcoal, and more rapid volatilization.

An ore of antimony. Like realgar and orpiment, a late low-temperature deposit of hot solutions, often associated with the arsenic minerals and cinnabar. The finest crystals ever found were brilliant needles over a foot long (30 cm) from the Ichinokawa Mine, Iyo Province (now Ehime Prefecture), n. Shikoku I., Japan. Almost their equal are those of Xikuangshan Antimony Mine in Hunan, China. Stubbier, bluntly terminated, fine 1-2-in. (2.5-5 cm) crystals in crusts and radiating clusters come from Baia Sprie (Felsöbanya), Romania. The best U.S. crystals have been found at Manhattan, Nye Co., Nevada. A few large crystals, nearly like those of China, have been found in Huarás, Peru.

Giant ocherous pseudomorphs, now two Sb oxides--cervantite (Sb ₂ O ₄ ) and stibiconite (Sb ₃ O ₆ [OH])--give hope for some eventual fine stibnites from sources near Oaxaca, Mexico.

Stibnite is the outstanding example of a mineral showing the phenomenon of well-developed gliding planes. Slipping directions are so well developed that many of the crystals found in nature are bent, or soon become bent, without fracturing. The atoms will glide a definite distance in the basal plane and then stop. (See calcite and vivianite.)

• Mineral compounds

Stibnite
Stibnite in the Carnegie Museum of Natural History
General
Category	Sulfide mineral
Chemical formula	Sb2S3
Strunz classification	02.DB.05a
Crystal symmetry	Orthorhombic dipyramidal H-M symbol: (2/m 2/m 2/m) Space group: Pbnm
Unit cell	a = 11.229 Å, b = 11.31 Å, c = 3.8389 Å; Z = 4
Identification
Color	Lead-gray, tarnishing blackish or iridescent; in polished section, white
Crystal habit	Massive, radiating and elongated crystals. Massive and granular
Crystal system	Orthorhombic
Twinning	Rare
Cleavage	Perfect and easy on {010}; imperfect on {100} and {110}
Fracture	Subconchoidal
Tenacity	Highly flexible but not elastic; slightly sectile
Mohs scale hardness	2
Luster	Splendent on fresh crystals surfaces, otherwise metallic
Streak	Similar to color
Diaphaneity	Opaque
Specific gravity	4.63
Solubility	decomposed with hydrochloric acid
Other characteristics	Anisotropism: Strong
References	[1][2][3]
Major varieties
Metastibnite	Earthy, reddish deposits

Stibnite, sometimes called antimonite, is a sulfide mineral with the formula Sb₂S₃. This soft grey material crystallizes in an orthorhombic space group. It is the most important source for the metalloid antimony.^[4] The name is from the Greek stibi through the Latin stibium as the old name for the mineral and the element antimony.^[1][2] As an antimony sulfide, it is potentially toxic and should be handled with care.

Contents 1 Structure 2 Uses 3 Occurrence 4 See also 5 References 6 External links

Structure

Crystals from Henan Province, China (size: 16.8×5.4×5.4 cm)

Stibnite has a structure similar to that of arsenic trisulfide, As₂S₃. The Sb(III) centers, which are pyramidal and three-coordinate, are linked via bent two-coordinate sulfide ions. It is grey when fresh, but can turn superficially black due to oxidation in air.

Uses

Pastes of Sb₂S₃ powder in fat^[5] or in other materials have been used since ca. 3000 BC as eye cosmetics in the Middle East and farther afield; in this use, Sb₂S₃ is called kohl. It was used to darken the brows and lashes, or to draw a line around the perimeter of the eye.

Antimony trisulfide finds use in pyrotechnic compositions, namely in the glitter and fountain mixtures. Needle-like crystals, "Chinese Needle", are used in glitter compositions and white pyrotechnic stars. The "Dark Pyro" version is used in flash powders to increase their sensitivity and sharpen their report. It is also a component of modern safety matches. It was formerly used in flash compositions, but its use was abandoned due to toxicity and sensitivity to static electricity.^[6]

The natural sulfide of antimony, stibnite, was known and used ever since protodynastic Ancient Egypt as a medication and a cosmetic. The Sunan Abi Dawood reports, “prophet Muhammad said: 'Among the best types of collyrium is antimony (ithmid) for it clears the vision and makes the hair sprout.'”^[7]

The 17th century alchemist Eirenaeus Philalethes, also known as George Starkey, describes stibnite in his alchemical commentary "An Exposition upon Sir George Ripley's Epistle." Starkey used stibnite as a precursor to philosophical mercury, which was itself a hypothetical precursor to the Philosopher's stone^[8]

Occurrence

Needles of stibnite within a transparent crystal of calcite (size: 4.5×3.5×1.8 cm)

Stibnite occurs in hydrothermal deposits and is associated with realgar, orpiment, cinnabar, galena, pyrite, marcasite, arsenopyrite, cervantite, stibiconite, calcite, ankerite, barite and chalcedony.^[1]

Small deposits of stibnite are common, but large deposits are rare. It occurs in Canada, Mexico, Peru, Japan, China, Germany, Romania, Italy, France, England, Algeria, and Kalimantan, Borneo. In the United States it is found in Arkansas, Idaho, Nevada, California, and Alaska.

As of May 2007, the largest specimen on public display (1000 pounds) is at the American Museum of Natural History.^[9][10] The largest documented single crystals of stibnite measured ~60×5×5 cm and originated from different locations including Japan, France and Germany.^[11]

See also

• List of minerals

Wikimedia Commons has media related to: Stibnite

References

1. ^ ^{a b c} Stibnite. Handbook of Mineralogy
2. ^ ^{a b} Stibnite. Mindat.org
3. ^ Stibnite. Webmineral
4. ^ Sabina C. Grund, K. Hanusch, H. J. Breunig, H. U. Wolf, “Antimony and Antimony Compounds” in Ullmann’s Encyclopedia of Industrial Chemistry 2006, Wiley-VCH, Weinheim. doi:10.1002/14356007.a03 055.pub2
5. ^ Priesner, Claus and Figala, Karin, ed. (1998) (in German). Alchemie. Lexikon einer hermetischen Wissenschaft. München: C.H. Beck. ISBN 3-406-44106-8. 
6. ^ Pyrotechnic Chemical Guide. PyroUniverse.com. Retrieved on 2011-10-14.
7. ^ Sunan Abu-Dawud (Ahmad Hasan translation). Book 32, Number 4050. http://www.muslimaccess.com/sunnah/hadeeth/abudawud/032.html. 
8. ^ Eirenaeus Philalethes and Carl Jung http://www.persee.fr/web/revues/home/prescript/article/rhs_0151-4105_1996_num_49_2_1254
9. ^ "American Museum of Natural History, Spectacular Stibnite". American Museum of Natural History. http://www.amnh.org/science/papers/stibnite.php. Retrieved 2007-05-27. 
10. ^ "Chinese stibnite crystal on display in US". http://www.cctv.com/program/cultureexpress/20070406/100505.shtml. Retrieved 2009-06-06. 
11. ^ P. C. Rickwood (1981). "The largest crystals". American Mineralogist 66: 885–907. http://www.minsocam.org/ammin/AM66/AM66_885.pdf. 

External links

 Chisholm, Hugh, ed. (1911). "Stibnite". Encyclopædia Britannica (11th ed.). Cambridge University Press. 

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