Editing Platinum group (section)

===Platinum===
[[Platinum]] can occur as a native metal, but it can also occur in various different minerals and alloys.<ref>{{Cite web|url=https://www.bgs.ac.uk/downloads/start.cfm?id=1401|title=Mineral Profile: Platinum|date=September 2009|website=British Geological Survey|access-date=6 February 2018}}</ref><ref>{{Cite web|url=https://www.mindat.org/chemsearch.php?inc=Pt|title=Search Minerals By Chemistry - Platinum|website=www.mindat.org|access-date=2018-02-08}}</ref> That said, [[Sperrylite]] (platinum [[arsenide]], PtAs<sub>2</sub>) [[ore]] is by far the most significant source of this metal.<ref>{{Cite web|url=https://uwaterloo.ca/earth-sciences-museum/resources/detailed-rocks-and-minerals-articles/platinum|title=Platinum {{!}} Earth Sciences Museum {{!}} University of Waterloo|last=Feick|first=Kathy|website=University of Waterloo|date=28 February 2013 |access-date=6 February 2018}}</ref> A naturally occurring platinum-iridium alloy, platiniridium, is found in the [[mineral]] [[Cooperite (mineral)|cooperite]] (platinum [[sulfide]], PtS). Platinum in a native state, often accompanied by small amounts of other platinum metals, is found in [[alluvium|alluvial]] and [[placer deposit|placer]] deposits in [[Colombia]], [[Ontario]], the [[Ural Mountains]], and in certain western [[United States|American]] states. Platinum is also produced commercially as a by-product of [[nickel]] ore processing. The huge quantities of nickel ore processed makes up for the fact that platinum makes up only two parts per million of the ore. [[South Africa]], with vast platinum ore deposits in the [[Merensky Reef]] of the [[Bushveld igneous complex|Bushveld complex]], is the world's largest producer of platinum, followed by [[Russia]].<ref name="Xiao">{{cite journal |doi = 10.1016/j.mineng.2004.04.001 |journal = Minerals Engineering |volume = 17 |year = 2004 |pages = 961&ndash;979 |title =Characterizing and recovering the platinum group minerals—a review |first = Z. |last = Xiao |author2=Laplante, A. R.  |issue = 9–10|bibcode = 2004MiEng..17..961X }}</ref><ref name="Platinum-Geological_Survey">{{cite web |url=http://minerals.usgs.gov/minerals/pubs/commodity/platinum/platimcs07.pdf |title=Platinum&ndash;Group Metals |publisher=U.S. Geological Survey, Mineral Commodity Summaries |date=January 2007 |access-date=2008-09-09}}</ref> Platinum and palladium are also mined commercially from the [[Stillwater igneous complex]] in Montana, USA. Leaders of primary platinum production are South Africa and Russia, followed by Canada, Zimbabwe and USA.<ref>{{cite journal |last1=Bardi |first1=Ugo |last2=Caporali |first2=Stefano |title=Precious Metals in Automotive Technology: An Unsolvable Depletion Problem? |journal=Minerals |date=2014 |volume=4 |issue=2 |pages=388–398 |doi=10.3390/min4020388 |bibcode=2014Mine....4..388B |doi-access=free |hdl=2158/1086074 |hdl-access=free }}</ref>