Editing Cassiterite (section)

==Occurrence==
[[File:Cassiterite.jpg|thumb|left|Cassiterite [[bipyramids]], edge length {{circa|30 mm}}, [[Sichuan]], China]]
[[Image:Cassiterite - Blue Tier tinfield, Tasmania, Australia.jpg|thumb|left|Close up of cassiterite crystals, Blue Tier tinfield, [[Tasmania]], Australia]]

Most sources of cassiterite today are found in [[alluvium|alluvial]] or [[placer mining|placer]] deposits containing the weathering-resistant grains. The best sources of primary cassiterite are found in the tin mines of [[Bolivia]], where it is found in crystallised [[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>{{cite news |url=http://www.newsvine.com/_news/2008/11/01/2061627-mining-for-minerals-fuels-congo-conflict|title=Mining for minerals fuels Congo conflict |last=Watt |first=Louise |agency=[[Associated Press]] |date=2008-11-01 |access-date=2009-09-03|work=Yahoo! News |publisher=[[Yahoo!|Yahoo! Inc]]}}</ref><ref>{{cite news
 | 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]].

Cassiterite is a widespread minor constituent of [[igneous rocks]]. The Bolivian veins and the 4500 year old workings of [[Cornwall]] and [[Devon]], [[England]], are concentrated in high temperature [[quartz]] veins and [[pegmatite]]s associated with [[granite|granitic]] [[Intrusive rock|intrusive]]s. 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.