Sudbury ores

These metals occur in both primary and secondary deposits. The primary deposits are generally associated with Ni-Cu sulfide ores. The Sudbury ores of Canada and the deposits of the Bushveld complex of South Africa are of this type. Native platinum occurs as a primary deposit in the Ural Mountains of the former U.S.S.R. and also in the Choco district of Colombia. Weathering and erosion of these deposits have resulted in the formation of secondary, or placer, deposits of native Pt in riverbeds and streams. One nugget of Pt found in Ihe Urals weighed over 25 pounds (11.3 kilograms). Most of the world s platinum comes from Canada, the former... 

Ontario Sudbury Ore deposits and mining wastes McGregor et al. (1998)... 

The reason for the rapid rise to importance of the Ontario deposits hs their tremendous extent. Whilst the New Caledonian ore may be estimated in hundreds of thousands of tons, the Ontario ores in the Sudbury area certainly reach seventy million tons, and possibly extend to at least twice that amount. In 1914 slightly more than one million metric tons of nickel ore were mined in Canada. Sudbury ore consists essentially of three minerals, namely, pyrrhotite, chalcopyrite, and pentlandite, accompanied by more or less rocky material of the nature of granite, quartzite, etc.3... 

A very important alloy containing 25 per cent, of nickel and 75 per cent, of copper finds extensive application in the manufacture of currency both in Europe and in the New World. Reference has already been made to this in previous pages.1 Monel metal is an alloy of nickel and copper made by the Orford Copper Company by direct reduction of the nickel-copper matte obtained from the Sudbury ores (see p. 82). It is therefore termed a natural alloy. It contains from 60-72 per cent, of nickel, the remainder consisting mainly of copper with iron ranging from 0-5 to 6-5 per cent. The United States Government specification, issued in July 1910, for monel metal requires 8... 

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 Sudbury region of Ontario, northwest of Lake Nipissing, has been the principal nickel-producing district in Canada since 1883. The Sudbury ore contains 1.5% Ni. Another large and established Canadian nickel deposit is that in Manitoba. Canadian geologists have continued to search for, and have even found, new areas of mineralization in their nickel-rich country. A huge nickel-copper-cobalt deposit has been discovered at Voisey s Bay in Labrador (not marked in Figure 31.4) and is now in development. 

Braggite [(Pt,Pd)S], cooperite [PtS], sperrylite [PtAs2], and Pt-Fe alloys are among the principal sources of PGE in the Bushveld complex. Michenerite [PdBiTe], moncheite [PdTe2], and sperrylite are common sources of PGE in some of the Sudbury ores, and all of the above minerals and many more have been reported to occur in the Noril sk deposits (Cabri, 1981). 

A member of the platinum group, ruthenium occurs native with other members of the group in ores found in the Ural mountains and in North and South America. It is also found along with other platinum metals in small but commercial quantities in pentlandite of the Sudbury, Ontario, nickel-mining region, and in pyroxinite deposits of South Africa. 

Osmium occurs in iridosule and in platinum-bearing river sands of the Urals, North America, and South America. It is also found in the nickel-bearing ores of Sudbury, Ontario region along with other platinum metals. While the quantity of platinum metals in these ores is very small, the large tonnages of nickel ores processed make commercial recovery possible. 

Ruthenium and osmium are generally found in the metallic state along with the other platinum metals and the coinage metals. The major source of the platinum metals are the nickel-copper sulfide ores found in South Africa and Sudbury (Canada), and in the river sands of the Urals in Russia. They are rare elements, ruthenium particularly so, their estimated abundances in the earth s crustal rocks being but O.OOOl (Ru) and 0.005 (Os) ppm. However, as in Group 7, there is a marked contrast between the abundances of the two heavier elements and that of the first. 

More than 200 ores are known to contain cobalt but only a few are of commercial value. The more important are arsenides and sulfides such as smaltite, C0AS2, cobaltite (or cobalt glance), CoAsS, and linnaeite, C03S4. These are invariably associated with nickel, and often also with copper and lead, and it is usually obtained as a byproduct or coproduct in the recovery of these metals. The world s major sources of cobalt are the African continent and Canada with smaller reserves in Australia and the former USSR. All the platinum metals are generally associated with each other and rhodium and iridium therefore occur wherever the other platinum metals are found. However, the relative proportions of the individual metals are by no means constant and the more important sources of rhodium are the nickel-copper-sulfide ores found in South Africa and in Sudbury, Canada, which contain about 0.1% Rh. Iridium is usually obtained from native osmiridium (Ir 50%) or iridiosmium (Ir 70%) found chiefiy in Alaska as well as South Africa. 

Although estimates of their abundances vary considerably, Pd and Pt (approximately 0.015 and 0.01 ppm respectively) are much rarer than Ni. They are generally associated with the other platinum metals and occur either native in placer (i.e. alluvial) deposits or as sulfides or arsenides in Ni, Cu and Fe sulfide ores. Until the 1820s all platinum metals came from South America, but in 1819 the first of a series of rich placer deposits which were to make Russia the chief source of the metals for the next century, was discovered in the Urals. More recently however, the copper-nickel ores in South Africa and Russia (where the Noril sk-Talnakh deposits are well inside the Arctic Circle) have become the major sources, supplemented by supplies from Sudbury. 

About 70% of the western world s supply of nickel comes from iron and nickel sulfide ores that were brought close to the surface nearly 2 billion years ago by the violent impact of a huge meteor at Sudbury, Ontario. The ore is first roasted (heated in air) to form nickel(II) oxide, which is reduced to the metal either elec-trolytically or by reaction with hydrogen gas in the first step of the Mond process ... 

Zhou ZA, Langlois R, Xu Z, Finch JA, Agnew R (1997) In-plant testing of a hydrodynamic reactor in flotation. In Finch JA, Rao SR, Huang LM (eds) Processing of Complex Ores. CIM, Sudbury, Canada, pp 185-193... 

More than 90% of the world s nickel is obtained from pentlandite ((FeNi)9S8), a nickel-sulfitic mineral, mined underground in Canada and the former Soviet Union (Sevin 1980 IARC 1976 WHO 1991). One of the largest sulfitic nickel deposits is in Sudbury, Ontario (USPHS 1993). Nickeliferous sulfide deposits are also found in Manitoba, South Africa, the former Soviet Union, Finland, western Australia, and Minnesota (Norseth and Piscator 1979 USPHS 1993). Most of the rest of the nickel obtained is from nickel minerals such as laterite, a nickel oxide ore mined by open pit techniques in Australia, Cuba, Indonesia, New Caledonia, and the former Soviet Union (Sevin 1980). Lateritic ores are less well defined than sulfitic ores, although the nickel content (1 to 3%) of both ores is similar (USPHS 1993). Important deposits of laterite are located in New Caledonia, Indonesia, Guatemala, the Dominican Republic, the Philippines, Brazil, and especially Cuba, which holds 35% of the known reserves (USPHS 1993). Nickel-rich nodules are found on the ocean floor, and nickel is also present in fossil fuels (Sevin 1980). 

Beaver ponds downstream from an abandoned copper-nickel ore roast yard near Sudbury, Ontario, were devoid of fish and had reduced macroinvertebrate taxon richness and diversity when compared to upstream ponds. Nickel water concentrations, in pg Ni/L, were 57 in upstream ponds,... 

Gypsy moth, Porthetria dispar, near ore smelter at Sudbury, Ontario, Canada vs. reference site ... 

Bagatto, G. and J.D. Shorthouse. 1996. Accumulation of Cu and Ni in successive stages of Lymantria dispar L. (Lymantriidae, Lepidoptera) near ore smelters at Sudbury, Ontario, Canada. Environ. Pollut. 92 7-12. 

Hillis, T.L. and G.H. Parker. 1993. Age and proximity to local ore-smelters as determinants of tissue metal levels in beaver (Castor canadensis) of the Sudbury (Ontario) area. Environ. Pollut. 80 67-72. 

Lepage, P. and G.H. Parker. 1988. Copper, nickel and iron levels in pelage of red squirrels living near the ore smelters at Sudbury, Ontario, Canada. Canad. Jour. Zool. 66 1631-1637. 

Other deposits of significant value as PGM carriers include the Kambalda district in Western Australia, the Pipe Mine in Thomson Manitoba, Canada, and the Hitura deposit in Finland. The mineralization of PGM in these ores is similar to that of the Sudbury region... 

The flotation of Cu-Ni and Ni ores is discussed in Chapter 16 (Volume 1). In most operating plants, the emphasis is usually placed on Cu-Ni and Ni recovery and concentrate grade, and most of the research on these ores was directed towards improvement in Cu-Ni recovery and pentlandite-pyrrhotite separation, whereas little or no attention was paid to improvement in recovery of PGM. In operations from the Sudbury Region (Canada), PGM are recovered as by-products of Cu-Ni concentrates. The idealized flowsheet of the Inco Metal PGM recovery flowsheet is shown in Figure 18.4. 

Laboratory studies conducted on Falconbridge ores, also from the Sudbury Region, during 1980 [16] showed that PGM recovery can be improved with the use of a secondary collector. Figure 18.5 shows the effect of level of secondary collector on PGM recovery in a Cu-Ni bulk concentrate. The highest PGM recoveries were achieved using isobutyl dithiophosphate (Minerec 2087) as the secondary collector. 

Ni-Cu-PGE mineralization at Sudbury is zoned with respect to Cu and PGE as a result of fractional crystallization from a base metal sulfide liquid, but metamorphism, fluids and deformation also affected these ore deposits (e.g., Farrow Lightfoot 2002 and authors therein). The two main styles of mineralization are 1) Fe-Ni-rich pyrrhotite ores (with minor pentlandite and chalcopyrite) in embayments along the base of the complex in noritic/gabbronoritic (contact ores) and 2) Cu-Pt-Pd-Au-rich chalcopyrite ores (with minor pentlandite, pyrrhotite and PGM) forming veins and stockworks in the country rock below the complex (footwall ores). Creighton Mine, on the southern margin of the complex, is one of the largest contact-style deposits. 

French explorers worked the La Motte Mine in Missouri for nickel as early as 1719 and during the period from 1830-50 shipped tire metal to refiners in England (125). Before the mining of nickel ores on tire island of New Caledonia in the Pacific was well developed in about 1877, nickel was so scarce that oies containing as little as one per cent of it could be worked profitably (125). The greatest nickel deposits in the world, those of the Sudbury district of Ontario, Canada, were discovered in about 1856 ( 23,125). 

Insoluble impurities fall to the floor of the cell as anode slime. Despite the derogatory name, this material contains precious metals such as gold, silver, and platinum. Anode slime from the electrorefining of nickel11 at Sudbury, Ontario, is a significant source of platinum and palladium as byproducts ( 0.34 g Pt and 0.36 g Pd per metric ton of ore), whereas deposits in the Bushveld complex (Transvaal, South Africa) are so rich in platinum-group metals (Ru, Os, Rh, Ir, Pd, Pt) that the associated Co, Ni, and Cu recovered are considered to be by-products of the lucrative platinum production (4.78 g Pt and 2.03 g Pd per metric ton of ore).7... 

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