What is Cassiterite?
[[File:Cassiterite - Mt Bischoff mine, Waratah, Tasmania, Australia.jpg|thumb|Cassiterite]] '''Cassiterite''' is a [[mineral]]. Its chemical formula is SnO<sub>2</sub>. It contains [[tin dioxide]]. It is black because of impurities. It is the main [[ore]] of [[tin]]. Its [[Mohs hardness]] is 6-7. {{science-stub}} [[Category:Minerals]]