Platinum
The platinum metals are extremely rare elements; platinum itself is the most common, with an abundance in the Earth's crust of about a millionth of 1 percent, whereas the others of the group have abundances of about one ten millionth of 1 percent.
Platinum is found in the fairly pure forms of small grains or nuggets, usually alloyed with other metals of its chemical group--iridium, osmium, palladium, rhodium, or ruthenium (PGE: platinum group elements) in dark rocks of iron-magnesium silicates (olivine, pyroxene, magnetite, chromite).
The only platinum compound known to occur in nature is the mineral ore sperrylite, or platinum arsenide.
Platinum is also found in quartz veins and in contact-metamorphic rocks. geology.wisc.edu
Platinum is often obtained as a by-product of the refining of nickel, gold, silver, and copper ores... "Finally, a situation which is of particular interest to Voisey Bay watchers. Earlier this year Falconbridge Ltd., the Avis of nickel, announced it would proceed with its Raglan development in northern Quebec. Raglan is located northwest of Voisey Bay and about 60 Km south of Ungava Bay on the Arctic coast. It has been known since 1965. In 1993, after about $35 million of exploration and underground development, an operating cost of US$2/lb (US$0.90/Kg) nickel was estimated from a mineable reserve base of 12.2 million tonnes of 3.7% nickel and 0.87% copper plus substantial platinum and palladium, plus a further 5.8 million tonnes of inferred reserve. In February a capital cost of $486 million was estimated before a production start in mid 1998. Concentrate will be shipped to Falconbridge's smelter. Unless exploration companies can sell a deposit to the Voisey Bay development this, more or less, is the target." The Hard Rock Analyst - November 30, 1995 Edition. stockgroup.com
Platinum does occur in hydrothermal deposits: earth.agu.org lib.udel.edu
* T. Evstigneeva, G.H. Moh, M. Tarkian, (1995): Hydrothermal recrystallization of PGE- and Fe-Ni-sulfide assemblages. N. Jb. Miner. Abh. 169, 3, 273-277. * T. Evstigneeva, M. Tarkian (1996): Synthesis of platinum-group minerals under hydrothermal conditions. Eur. J. Mineral. 8, 549-564. * Watkinson D.H. and Jones, P.C. (1995). Platinum-group minerals in fluid inclusions from the Marathon deposit, Coldwell Complex, Canada. Mineralogy and Petrology. * Farrow, C.E.G. and Watkinson, D.H. (1995) Geochemical evolution of the Epidote Zone, Fraser Mine, Sudbury, Ontario: Ni-Cu-PGE remobilization by saline fluids. Exploration and Mining Geology.
In the United States, the largest consumers of the metal are the chemical and electrical industries. Platinum catalysts are used in the commercial production of sulfuric and nitric acids as well as in the catalytic cracking process for refining petroleum...
For more information: mineral.galleries.com geology.wisc.edu minerals.er.usgs.gov mineral.galleries.com
Hope that helps, Patrick. |