Stibnite
| Stibnite | |
|---|---|
_Ehime,_Shikoku,_Japan_(DerHexer)_2012-07-20.jpg) exhibited in the Harvard Museum of Natural History |
|
| General and classification | |
| other names |
|
| chemical formula | Sb 2 S 3 |
|
Mineral class (and possibly department) |
Sulphides, sulphosalts - metal: sulfur (selenium, tellurium) <1: 1 |
|
System no. to Strunz and to Dana |
2.DB.05a ( 8th edition : II / C.02) 11/02/02/01 |
| Similar minerals | Enargite , manganite , zinkenite |
| Crystallographic Data | |
| Crystal system | orthorhombic |
| Crystal class ; symbol | orthorhombic-dipyramidal; 2 / m 2 / m 2 / m |
| Space group | Pnma (No. 62) |
| Lattice parameters | a = 11.311 Å ; b = 3.836 Å; c = 11.229 Å |
| Formula units | Z = 4 |
| Frequent crystal faces | Prisms (110) and (120), pyramids (111), (121) and (361), pinacoid (010) |
| Twinning | rarely after {120} and {130} |
| Physical Properties | |
| Mohs hardness | 2 ( VHN 100 = 71–86) |
| Density (g / cm 3 ) | measured: 4.63; calculated: 4.625 |
| Cleavage | perfect and easy according to {010} |
| Break ; Tenacity | slightly mussel-like; very flexible, but not elastic, slightly sectile |
| colour | steel to lead gray, tinged with different colors |
| Line color | lead gray |
| transparency | opaque |
| shine | Metal gloss, matt |
| Crystal optics | |
| Pleochroism | strong reflection pleochroism |
Stibnite , as antimonite or its mining designations stibnite or gray antimony or gray spit glass known, is a common mineral of the mineral class of "sulphides and thio" with the chemical composition of Sb 2 S 3 and chemical terms antimony (III) sulfide (also antimony trisulfide or short antimony sulfide ).
Stibnite crystallizes in the orthorhombic crystal system and usually develops short to long prismatic or needle-like crystals of a lead-gray color, which are typically striped lengthways and can reach lengths of over one meter. It is also found in the form of radial or granular to massive aggregates and rarely crystal twins . The Stibnitkristalle are always opaque ( opaque ) and have the fresh state on the surfaces of a strong metallic luster on.
Etymology and history
The mineral has been known since ancient times and was used as black make-up powder to color eyelids and eyebrows. Dark colored eye rims are considered an ideal of beauty in Arab culture and at the same time a magical means of defense. In ancient Greece it was also used to make bronze .
Antimonite was also used in Egypt from the 3rd millennium BC. Chr. As dark make-up. It has also been used as a remedy for eye diseases. Because there was no antimonite in Egypt at that time, it was also imported from Arabia and the Middle East at high prices.
In the Arabic-speaking world, al-kuhl ( Arabic الكحل, the coloring) the word for the traditional Arabic antimony make-up powder. Francis Bacon listed this powder made from a mineral under the term Alcohole in his "Sylva sylvarum; or a naturall historie" in 1626 .
The name antimonite has been used as a chemical name for the salts of antimonic acid since about 1834 and Wilhelm Haidinger derived the mineral name antimonite from it in 1845 .
The mineral name stibnite is derived from the Greek words Stimmi or stibi and the Latin word stibium , which denote this black, mineral powder. Based on the Latin stibium , François Sulpice Beudant introduced the name Stibine in 1832 , which was changed to Stibnite by James Dwight Dana in 1854 .
In German usage, the mineral names stibnite, antimonite and antimony gloss are used approximately equally.
classification
In the now outdated, but still in use 8th edition of the mineral classification according to Strunz , the stibnite belonged to the mineral class of "sulfides and sulfosalts" and there to the department of "sulfides with the molar ratio of metal: sulfur, selenium, tellurium <1: 1", where together with bismuthinite , guanajuatite , horobetsuit (now discredited as an intermediate member of the stibnite – bismuthinite series) and paxite the “antimonite series” with the system no. II / C.02 formed.
In the last revised and updated Lapis mineral directory by Stefan Weiß in 2018 , which, out of consideration for private collectors and institutional collections, is still based on this classic system of Karl Hugo Strunz , the mineral (here: antimonite ) was given the system and mineral number. II / D.08-20 , resulting in the "lapis classification" corresponds to the department, where it together with "sulfides with metal: 1: S, Se, Te <1" Antimonselit , Bismuthinit, Guanajuatit, Ottemannit and Pääkkönenit a common , but forms an unnamed group.
The 9th edition of Strunz's mineral systematics , which has been in effect since 2001 and was last updated by the International Mineralogical Association (IMA) in 2009, also assigns stibnite to the class of "sulfides and sulfosalts", although it has been expanded to include the related selenides , tellurides and arsenides , Antimonides , bismuthides , sulfarsenites , sulfantimonites and sulfbismuthites . The divisions of this class are partially redefined and further subdivided according to the exact ratio between metal and sulfur and / or the dominant metal ion of the compound. According to its composition, the mineral can be found in the department of “Metal sulfides with M: S = 3: 4 and 2: 3” and there in the subdivision “M: S = 2: 3”, where it is named after the “stibnite group “With the system no. 2.DB.05a and the other members antimony elite , bismuthinite, guanajuatite and metastibnite .
The systematics of minerals according to Dana , which is mainly used in the English-speaking world , assigns the stibnite to the class of "sulfides (and relatives)" and there in the department of "sulfide minerals". Here it is the eponymous mineral of the "stibnite group (Orthorhombic: Pbnm)" with the system no. 02.11.02 and the other members antimony elite , bismuthinite and guanajuatite within the subsection " Sulphides - including selenides and tellurides - with the composition A m B n X p , with (m + n): p = 2: 3 ".
Chemism
The idealized chemical composition of stibnite (Sb 2 S 3 ) consists of antimony (Sb) and sulfur (S) in a molar ratio of 2: 3, which gives a mass fraction of 71.68% by weight of Sb and 28.32% by weight S corresponds to. Usually the mineral can be found relatively pure , for example in Wolfsberg in Saxony-Anhalt with 71.45% by weight Sb and 28.42% by weight S. Occasionally, however, small foreign admixtures such as iron (Fe), copper (Cu) , Lead (Pb), zinc (Zn), cobalt (Co), silver (Ag) and / or gold (Au).
Crystal structure
Stibnite crystallizes orthorhombically in the space group Pnma (space group no. 62) with the lattice parameters a = 11.311 Å ; b = 3.836 Å and c = 11.229 Å and 4 formula units per unit cell .
The predominant structural motif are tetragonal SbS 5 pyramids. These form, so to speak, tetramers (arranged one inside the other in such a way that two with the tips pointing upwards, two pointing downwards), which extend infinitely along the b -direction with linked edges, hence the typical longitudinal stripes of the crystals and the very perfect cleavage parallel to this direction.
properties
In the air, the shine of the stibnit fades over time and becomes colorful . Over time, the mineral can also weather into yellow antimony ocher ( valentinite ) or antimony blossom , an earthy mixture of antimony oxides (mostly stibiconite or cervantite ).
In a thin section under the reflected light microscope, stibnite shows a strong reflection pleochroism. In the air it appears pale gray to white parallel to the a-axis, dark pale gray parallel to the b-axis with an olive tinge and pure white parallel to the c-axis. In oil, the pleochroistic effects are similar, albeit darker and clearer overall.
The Mohs hardness is 2 to 2.5 ( VHN 100 = 71 to 86 kg / mm²) and the density 4.6 to 4.7 g / cm³ , depending on the purity .
Stibnite is sometimes confused with galena , but differs from it in that stibnite melts in the flame of a match (melting point: approx. 548 to 550 ° C). It burns with a green-blue flame.
In hydrochloric acid and hot aqueous sodium sulfide solution is Stibnit soluble and in nitric acid it decomposes with separation of Sb 2 S 5 .
Modifications and varieties
The compound Sb 2 S 3 is dimorphic , which means that in nature it occurs as an amorphous metastibnite in addition to the orthorhombic crystallizing stibnite .
Education and Locations
Stibnite forms in hydrothermal ore veins in a wide temperature range between approximately 300 and 1000 ° C. There it occurs in paragenesis with many other sulfide minerals such as arsenopyrite , auripigment , cinnabarite , galena , marcasite , pyrite , realgar , but also with anchorite , calcite , barite , cervantite , fluorite , stibiconite and quartz (mostly in the form of chalcedony ) .
As a frequent mineral formation, stibnite can be found at many sites, with over 3000 sites known to date (as of 2016).
The antimony deposit near Xikuangshan in the Chinese province of Hunan , in which crystals over a meter long were found, and the "Ichinokawa Mine" on Shikoku in Japan, from which crystals up to 60 cm long emerged, are known for their extraordinary mineral finds. The “White Caps Mine” near Manhattan ( Nye County ) in Nevada also delivers large crystals of up to 20 cm in length and at Kadamdzhai in Kyrgyzstan crystal glands with a diameter of up to 15 cm have been found in which stibnite is often mixed with fluorite, barite and calcite is socialized.
In Germany the mineral was found in antimonite-quartz veins (partly also with gold ) at Brandholz / Goldkronach in Bavaria and Schleiz in Thuringia, in lead - silver veins such as at Bräunsdorf near Freiberg in Saxony and Wolfsberg in the Harz Mountains in Saxony-Anhalt. In addition, many other sites are known in the Black Forest (Baden-Württemberg), the Sauerland and Siegerland (North Rhine-Westphalia), the Eifel (Rhineland-Palatinate) and the Ore Mountains (Saxony).
A well-known site in Austria is the antimony mine near Stadtschlaining in Burgenland with crystal finds several centimeters in size. In addition, stibnite can be found in varying quantities and sometimes forming deposits in Carinthia , Lower Austria , Salzburg , Styria and Tyrol .
Larger deposits were or are also located in the Auvergne in central France, Algeria , Bolivia , near Lesniča on the Drina in Bosnia, Italy , in the northern Transvaal in South Africa as well as in the Czech Republic and Slovakia (formerly Czechoslovakia , ČSSR). In the Chinese deposits in the provinces of Guangxi ( Kwangsi ), Guizhou ( Kweichow ) and Hunan Antimonit usually occurs in quartz courses on along with cinnabar and pyrite as well as replacement deposits with galena.
Stibnite finds from Switzerland are known from the cantons of Graubünden , Ticino and Valais , among others .
Other sites are found in the Antarctic , Argentina , Australia , Bosnia and Herzegovina , Brazil , Bulgaria , Chile , Costa Rica , Ecuador , Fiji , Finland , France , Georgia , Ghana , Greece , Guatemala , India , Indonesia , Iran , Ireland , Isle of Man , Cambodia , Canada , Jersey Channel Island , Kazakhstan , Kyrgyzstan , Kosovo , Colombia , Cuba , Laos , Luxembourg , Madagascar , Malaysia , Morocco , Mexico , Mongolia , Namibia , New Caledonia , New Zealand , Niger , North Macedonia , Norway , Pakistan , Papua New Guinea , Peru , the Philippines , Poland , Portugal , Romania , Russia , Saudi Arabia , Sweden , Serbia , Zimbabwe , Slovenia , Spain , South Korea , Tajikistan , Tanzania , Taiwan , Thailand , Turkey , Ukraine , Hungary , Uzbekistan , the United Kingdom (Great Britain) and the United States of America (USA).
use
The mineral is of economic importance due to its high antimony content of up to 71.7%. This very rare metal , which only makes up 0.00002% of the earth's crust and is used as an alloying element in hardened gear steel , as an admixture in battery lead and in the semiconductor industry, is mainly extracted from stibnite. The main exporter in 2003 was the People's Republic of China .
See also
literature
- Hans Jürgen Rösler : Textbook of Mineralogy . 4th revised and expanded edition. German publishing house for basic industry (VEB), Leipzig 1987, ISBN 3-342-00288-3 , p. 337-338 .
- Helmut Schrätze , Karl-Ludwig Weiner : Mineralogy. A textbook on a systematic basis . de Gruyter, Berlin; New York 1981, ISBN 3-11-006823-0 , pp. 232-235 .
- Martin Okrusch, Siegfried Matthes: Mineralogy. An introduction to special mineralogy, petrology and geology . 7th, completely revised and updated edition. Springer, Berlin [a. a.] 2005, ISBN 3-540-23812-3 , pp. 37, 266 .
- LJ Spencer: Some Mineral Names . In: American Mineralogist . tape 22 , 1937, pp. 682–685 (English, PDF 271 kB).
- Petr Korbel, Milan Novák: Mineral Encyclopedia (= Villager Nature ). Edition Dörfler im Nebel-Verlag, Eggolsheim 2002, ISBN 978-3-89555-076-8 , p. 39 .
Web links
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Mineral Atlas :
- Stibnite (antimonite)
- Mineral portrait of stibnite
- Mineral records
- Stibnite search results. In: rruff.info. Database of Raman spectroscopy, X-ray diffraction and chemistry of minerals (RRUFF), accessed on August 18, 2020 .
- American-Mineralogist-Crystal-Structure-Database - Stibnite. In: rruff.geo.arizona.edu. Accessed August 18, 2020 .
Individual evidence
- ↑ a b c d e f Hans Lüschen: The names of the stones. The mineral kingdom in the mirror of language . 2nd Edition. Ott Verlag, Thun 1979, ISBN 3-7225-6265-1 , p. 232, 323 .
- ↑ a b c P. Bayliss, W. Nowacki: Refinement of the crystal structure of stibnite, Sb 2 S 3 . In: Journal of Crystallography . tape 135 , 1972, pp. 308-315 , doi : 10.1524 / zkri.1972.135.3-4.308 .
- ↑ a b c d e f g Hans Jürgen Rösler : Textbook of Mineralogy . 4th revised and expanded edition. German publishing house for basic industry (VEB), Leipzig 1987, ISBN 3-342-00288-3 , p. 337-338 .
- ↑ a b c d e Stibnite . In: John W. Anthony, Richard A. Bideaux, Kenneth W. Bladh, Monte C. Nichols (Eds.): Handbook of Mineralogy, Mineralogical Society of America . 2001 (English, handbookofmineralogy.org [PDF; 111 kB ; accessed on August 18, 2020]).
- ↑ Sigrid Jungbluth-Opota: Influence of Wecesin® powder containing antimony on the vitality, O 2 - production and the microbial killing capacity of human granulocytes in vitro . Medical Faculty of Heinrich Heine University, Düsseldorf 2007, p. 6 ( docserv.uni-duesseldorf.de [PDF; 3.5 MB ; accessed on August 18, 2020] Dissertation, Clinic for General Pediatrics of the Heinrich Heine University Düsseldorf).
- ↑ a b c LJ Spencer: Some Mineral Names . In: American Mineralogist . tape 22 , 1937, pp. 682–685 ( minsocam.org [PDF; 277 kB ; accessed on August 18, 2020]).
- ↑ Willem Frans Daems: stimmi - Stibium - antimony. A substance-historical consideration (= Weleda series of publications . Volume 9 ). Weleda, Arlesheim and Schwäbisch Gmünd 1976.
- ^ FS Beudant: Traité élémentaire de minéralogie . Verdière, Paris 1832.
- ↑ a b Stefan Weiß: The large Lapis mineral directory. All minerals from A - Z and their properties. Status 03/2018 . 7th, completely revised and supplemented edition. Weise, Munich 2018, ISBN 978-3-921656-83-9 .
- ^ Ernest H. Nickel , Monte C. Nichols: IMA / CNMNC List of Mineral Names. (PDF 1815 kB) In: cnmnc.main.jp. IMA / CNMNC, January 2009, accessed April 18, 2019 .
- ↑ Stibnite. In: Mineralienatlas Lexikon. Stefan Schorn u. a., accessed on August 18, 2020 .
- ↑ Paul Ramdohr : The ore minerals and their adhesions . 4th, revised and expanded edition. Akademie-Verlag, Berlin 1975, p. 757 .
- ↑ Stibnite. In: mindat.org. Hudson Institute of Mineralogy, accessed August 18, 2020 .
- ↑ a b c Helmut Schrätze , Karl-Ludwig Weiner : Mineralogie. A textbook on a systematic basis . de Gruyter, Berlin; New York 1981, ISBN 3-11-006823-0 , pp. 232-235 .
- ↑ Localities for Stibnite. In: mindat.org. Hudson Institute of Mineralogy, accessed August 18, 2020 .
- ↑ a b List of locations for stibnite from the Mineralienatlas and Mindat , accessed on August 18, 2020.
- ^ David Barthelmy: Stibnite Mineral Data. In: webmineral.com. Retrieved on August 19, 2020 (English).