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{{short description|Tin oxide mineral, SnO₂}}
CASSITERITE'''Cassiterite''' is a [[tin]] [[oxide mineral]], [[Tin dioxide|SnO<sub>2</sub>]]. It is generally [[Opacity (optics)|opaque]], but it is translucent in thin crystals. Its [[Lustre (mineralogy)|luster]] and multiple crystal faces produce a desirable gem. Cassiterite was the chief tin [[ore]] throughout [[Tin sources and trade in ancient times|ancient history]] and remains the most important source of tin today.▼
{{Infobox mineral
| name = Cassiterite
| category = [[Oxide minerals]]
| boxwidth =
| boxbgcolor =
| image = 4447M-cassiterite.jpg
| imagesize =
| caption = Cassiterite with [[muscovite]], from Xuebaoding, Huya, Pingwu, Mianyang, Sichuan, China (size: 100 x 95 mm, 1128 g)
| formula = SnO<sub>2</sub>
| IMAsymbol=Cst<ref>{{Cite journal|last=Warr|first=L.N.|date=2021|title=IMA–CNMNC approved mineral symbols|journal=Mineralogical Magazine|volume=85|issue=3|pages=291–320|doi=10.1180/mgm.2021.43|bibcode=2021MinM...85..291W|s2cid=235729616|doi-access=free}}</ref>
| molweight =
| strunz = 4.DB.05
| system = [[Tetragonal]]
| class = Ditetragonal dipyramidal (4/mmm) <br/>[[H-M symbol]]: (4/m 2/m 2/m)
| symmetry = ''P4''<sub>2</sub>/mnm
| unit cell = a = 4.7382(4) Å, <br/>c = 3.1871(1) Å; Z = 2
| color = Black, brownish black, reddish brown, brown, red, yellow, gray, white; rarely colorless
| habit = Pyramidic, prismatic, radially fibrous botryoidal crusts and concretionary masses; coarse to fine granular, massive
| twinning = Very common on {011}, as contact and penetration twins, geniculated; lamellar
| cleavage = {100} imperfect, {110} indistinct; partings on {111} or {011}
| fracture = Subconchoidal to uneven
| tenacity = Brittle
| mohs = 6–7
| luster = Adamantine to adamantine metallic, splendent; may be greasy on fractures
| refractive = n<sub>ω</sub> = 1.990–2.010 n<sub>ε</sub> = 2.093–2.100
| opticalprop = Uniaxial (+)
| birefringence = δ = 0.103
| pleochroism = Pleochroic haloes have been observed. Dichroic in yellow, green, red, brown, usually weak, or absent, but strong at times
| streak = White to brownish
| gravity = 6.98–7.1
| density =
| melt =
| fusibility = infusible
| diagnostic =
| solubility = insoluble
| diaphaneity = Transparent when light colored, dark material nearly opaque; commonly zoned
| other =
| references = <ref>[https://www.mineralienatlas.de/lexikon/index.php/MineralData?mineral=Cassiterite Mineralienatlas]</ref><ref name=Handbook>{{cite web |last1=Anthony |first1=John W. |last2=Bideaux |first2=Richard A. |last3=Bladh |first3=Kenneth W. |last4=Nichols |first4=Monte C. |title=Cassiterite |url=http://www.handbookofmineralogy.org/pdfs/cassiterite.pdf |website=Handbook of Mineralogy |publisher=Mineral Data Publishing |access-date=19 June 2022 |date=2005}}</ref><ref name=Mindat>{{mindat|id=917|title=Cassiterite}}</ref><ref name=Webmin>[http://webmineral.com/data/Cassiterite.shtml Webmineral]</ref><ref name=Klein>{{cite book |last1=Hurlbut |first1=Cornelius S. |last2=Klein |first2=Cornelis |year=1985 |title=Manual of Mineralogy |edition=20th |publisher=John Wiley and Sons |location=New York |pages=[https://archive.org/details/manualofmineralo00klei/page/306 306–307] |isbn=0-471-80580-7 |url-access=registration |url=https://archive.org/details/manualofmineralo00klei/page/306 }}</ref>
}}
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==
[[File:Cassiterite.jpg
[[
<s>Most sources of cassiterite today are found in [[Alluvium|alluvial]] or [[Placer mining|placer]] deposits containing the resistant weathered grains. The best sources of primary cassiterite are found in the tin mines of [[Bolivia]], where it is found in [[hydrothermal]] veins. [[Rwanda]] has a nascent cassiterite mining industry. Fighting over cassiterite deposits (particularly in [[Walikale]]) is a major cause of the conflict waged in eastern parts of the [[Democratic Republic of the Congo]].<ref /><ref /> This has led to cassiterite being considered a [[conflict mineral]].</s>▼
▲
<s>Cassiterite is a widespread minor constituent of [[igneous rocks]]. The Bolivian veins and the old exhausted workings of [[Cornwall]], [[England]], are concentrated in high temperature [[quartz]] veins and [[Pegmatite|pegmatites]] associated with [[Granite|granitic]] [[Intrusive rock|intrusives]]. The veins commonly contain [[tourmaline]], [[topaz]], [[fluorite]], [[apatite]], [[wolframite]], [[molybdenite]], and [[arsenopyrite]]. The mineral occurs extensively in [[Cornwall]] as surface deposits on [[Bodmin Moor]], for example, where there are extensive traces of a hydraulic mining method known as ''streaming''. The current major tin production comes from placer or alluvial deposits in [[Malaysia]], [[Thailand]], [[Indonesia]], the [[Maakhir]] region of [[Somalia]], and [[Russia]]. [[Hydraulic mining]] methods are used to concentrate mined ore, a process which relies on the high [[specific gravity]] of the SnO<sub>2</sub> ore, of about 7.0.</s>▼
| last = Polgreen
| first = Lydia
| title = Congo's Riches, Looted by Renegade Troops
| work=[[The New York Times]]
| date = 2008-11-16
| url = https://www.nytimes.com/2008/11/16/world/africa/16congo.html?pagewanted=1&_r=1&th&emc=th
| access-date = 2008-11-16}}</ref> This has led to cassiterite being considered a [[conflict mineral]].
▲
== <s>Crystallography</s> ==▼
[[File:Rutile-unit-cell-3D-balls.png|left|thumb|Crystal structure of cassiterite]]▼
<s>[[Crystal twinning]] is common in cassiterite and most aggregate specimens show crystal twins. The typical twin is bent at a near-60-degree angle, forming an "elbow twin". [[Botryoidal]] or reniform cassiterite is called ''wood tin''.</s>▼
<s>Cassiterite is also used as a [[gemstone]] and collector specimens when quality crystals are found.</s>▼
[[File:Cassiterite-43265.jpg|left|thumb|Stalactitic-botryoidal, banded, "wood tin" cassiterite, 5.0 x 4.9 x 3.3 cm, [[Durango]], Mexico]]▼
▲[[File:Cassiterite_-_Blue_Tier_tinfield,_Tasmania,_Australia.jpg|thumb|Close up of cassiterite crystals, Blue Tier tinfield, [[Tasmania]], Australia]]
▲
▲
▲[[File:Cassiterite-43265.jpg
▲== <s>Etymology</s> ==
▲<s>The name derives from the [[Greek language|Greek]] ''kassiteros'' for "tin": this comes from the [[Phoenician languages|Phoenician]] word ''Cassiterid'' referring to the islands of [[Ireland]] and [[Great Britain]],<sup>[''[[wikipedia:Citation needed|citation needed]]'']</sup> the ancient sources of tin; or, as [[Roman Ghirshman]] (1954) suggests, from the region of the [[Kassites]], an ancient people in west and central [[Iran]].</s>
{{clear}}
==
It may be primary used as a raw material for [[tin]] extraction and smelting.
==References==
== <s>External links</s> ==▼
{{reflist|25em}}
{{Commons category|Cassiterite}}{{Ores}}▼
{{Ores}}
{{Authority control}}
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