Platinum group elements deposits

Cawthom RG (2010) The platinum group element deposits of the Bushveld Complex in South Africa. Platinum Met Rev 54(4) 205-215... 

Naldrett, A.J., Platinum Group Elements, In (Cabri, L.J. ed) Deposits of Platinum Group Elements Mineralogy, Geology and Recovery. Johannesburg, South Africa, CIM Special Volume 23, Chapter 10, pp. 198-230, 1981. 

Barnes, S.J., Prichard, H.P., Cox, R.A., Fisher, P.C., Godel, B. 2008. The location of the chalcophile and siderophile elements in platinum-group elements ore deposits (a textural, microbeam and whole rock geochemical study) Implication for the formation of ore deposits. Chemical Geology, 248, 295-317. 

Quantitative mass balance of platinum-group elements in the Kelly Lake Ni-Cu-PGE deposit. Copper Cliff Offset, Sudbury. Economic Geology, 100, 1631-1646. 

Platinum-190 decays to 186Os by emission of an a-particle. Both are platinum-group elements and thus the system has potential use for iron meteorites and PGE-bearing mineral deposits. Walker et al. (1997) determined the decay constant of 190Pt (X =(1.542 0.015) x 10 12 yr half-life =4.5 x 1011 years) and established parameters for... 

In a limestone deposit at Kinnekulle, Sweden, a remarkable collection of more than 40 highly altered meteorites (Fig. 9.18) totaling 7.7 kg have been collected during routine guarrying operations (Schmitz etal., 1997,2001,2003). The 3.2-m-thick limestone layer in which they are found was deposited over -1.75 Myr in the mid-Ordovician. Despite being almost completely replaced by calcite, barite, and phyllosilicates, the meteorites are easily identified by their chondritic texture. Their identification as meteorites is confirmed by measurements of platinum-group elements. The chemical characteristics of relict spinels indicate that they are either L or LL chondrites. 

Cave R. R., Ravizza G. E., German C. R., Thomson J., and Nesbitt R. W. (2003) Deposition of osmium and other platinum-group elements beneath the ultramafic-hosted rainbow hydrothermal plume. Earth Planet. Sci. Lett. 210, 65-79. 

Stuben, D., Glasby, GP, Eckhardt, J.-D., Berner, Z., Mountain, B.W. and Usui, A., 1999. Enrichments of platinum-group elements in hydrogenous, diagenetic and hydrothermal marine manganese and iron deposits. Exploration and Mining Geology, 8 233-250. 

Clay Mineralogy. Hydrothermal Vent Deposits. Platinum Group Elements and their Isotopes in the Ocean. Pore Water Chemistry. Rare Earth Elements and their Isotopes in the Ocean. River Inputs. Tracers of Ocean Productivity. Transition Metals and Heavy Metal Speciation. Uranium-Thorium Decay Series in the Oceans Overview. 

The electrochemical deposition of a metallic-ruthenium film is very difficult compared with that of other platinum-group elements [46, 61, 91-93]. One of the reasons may be related to the comphcated electrochemistry of ruthenium deposition and the stability of the Ru-chloro complex [92]. For example, it has been reported that the RuCfi species in HCIO4 solution is decomposed partly into RuO +, in which Ru(IV) is present [94]. 

Rhodium, as befits an element of the platinum metal sextet, occurs mainly as a minor constituent of platinum group metal ores. Thus, it occurs as a component of the ore deposits at Sudbury, Ontario, in the Merensky reef at Rustenberg in the Republic of South Africa, and in the platinum metals ore deposits in the Ural range of the USSR. The major production centers are the Urals and South Africa, since the Sudbury ores in particular have a very low rhodium content. Minor deposits of the metal ores which contain some rhodium also occur in British Columbia, the United States of America, Columbia, Spain, Borneo and Australia. Nevertheless, rhodium is an exceedingly rare element with an abundance in the earth s crust of some 10 9%. 

The platinum-group metals consist of ruthenium, rhodium, palladium, osmium, iridium, and platinum. Each of the metals occurs naturally in its native form, and in economically exploitable deposits the elements occur overwhelmingly as individual platinum-group mineral (PGM) species. Mutual substitution of the various PGE is common, but substitutions in other minerals, such as base-metal sulfides, typically occur to only a limited extent. A comprehensive review of PGM and PGE geochemistry is given by Cabri (2002). 

The potential mineral resources of the Transantarctic Mountains, including metallic and radioactive minerals as well as coal in the Beacon Supergroup, were discussed in Section 11.5. We now turn to the Dufek intrusion which contains several important metals Iron, titanium, chromium, vanadium, copper, cobalt, nickel, and members of the platinum group of elements. Although the Dufek intrusion is an attractive target for mineral exploration. Ford (1990) emphasized that no minable deposits of any kind are currently known to exist there. The scientific merits of drilling the Dufek intrusion were discussed in 1979 by the Committee on Eneigy and Natural Resources of the US. Senate, but these discussions were terminated becanse of concern about contamination of the environment. 

The platinum group metals occur jointly as alloys and as mineral compounds in placer deposits of varying compositions. Ru and Os are separated from the PGM mix by distillation of their volatile oxides, whereas platinum, iridium, palladium, and rhodium are separated by repeated solution and precipitation as complex PGM chlorides, or by solvent extraction and thermal decomposition to sponge or powder. PGM scrap is recycled by melting with collector metals (lead, iron, or copper) followed by element-specific extraction. 

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