Editing Platinum group (section)

===Rhodium===
The industrial extraction of [[rhodium]] is complex, because it occurs in ores mixed with other metals such as palladium, [[silver]], platinum, and [[gold]]. It is found in platinum ores and obtained free as a white inert metal which is very difficult to fuse. Principal sources of this element are located in South Africa, Zimbabwe, in the river sands of the [[Ural Mountains]], North and South America, and also in the copper-nickel sulfide mining area of the [[Sudbury Basin]] region. Although the quantity at Sudbury is very small, the large amount of nickel ore processed makes rhodium recovery cost effective. However, the annual world production in 2003 of this element is only 7 or 8 [[ton]]s and there are very few rhodium minerals.<ref name="NRC">{{cite web |publisher = Natural Resources Canada |title = Platinum Group Metals |first = Patrick |last = Chevalier |url = http://www.nrcan.gc.ca/mms-smm/busi-indu/cmy-amc/content/2004/71.pdf |access-date = 2008-10-17 |url-status = dead |archive-url = https://web.archive.org/web/20110811170221/http://www.nrcan.gc.ca/mms-smm/busi-indu/cmy-amc/content/2004/71.pdf |archive-date = 2011-08-11 }}</ref>