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Platinum Group Elements
Content maintained by Yanis Miezitis
The platinum group elements (PGE) comprise platinum (Pt), palladium (Pd), iridium (Ir), osmium (Os), rhodium (Rh) and ruthenium (Ru). The elements of most commercial significance are platinum, palladium and, to a lesser degree, rhodium. The properties of PGEs’ which have commercial importance include their resistance to corrosion and oxidation, high-melting points, electrical conductivity and catalytic activity in the chemical, electrical, electronic, glass and motor vehicle industries. The emerging commercial importance of PGEs is in applications associated with the motor vehicle industry resulting from increasing global emission controls, development of lead-free petrol and efforts to improve fuel efficiency. Other applications include the use of platinum-rhodium alloys to oxidise ammonia to nitric acid in the production of fertilisers, while platinum is used extensively in jewellery.
According to figures published by Matthey (2013)1, gross demand for platinum fell marginally in 2012 to 8.05 million ounces (Moz) with higher jewellery demand offset by sharply lower industrial buying. Demand for platinum in auto-catalyst applications rose slightly in 2012 to 3.24 Moz. The demand for platinum in jewellery increased by 305 000 ounces (oz) to 1.57 Moz while the gross industrial demand for platinum fell by 405 000 oz in 2012. Net identifiable physical demand for platinum in the investment sector reached 455 000 oz in 2012, about 5000 oz lower than in 2011.
Gross demand for palladium increased by 16% to 9.90 Moz in 2012. Gross demand for palladium from the auto-catalyst sector in 2012 reached an all-time high level of 6.62 Moz as a result of greater use of palladium in light duty gasoline vehicles in China and another rise in the ratio of palladium to platinum in autoclasts for European diesel vehicles. Demand for palladium in industrial applications fell by 100 000 oz to 2.365 Moz, while demand for jewellery fell by 60 000 oz to 445 000 oz but net physical investment demand switched from a negative of 565 000 to a positive of 470 000 or an increase of more than 1 Moz to 470 000 oz in 2012.
Australia's Economic Demonstrated Resources (EDR) of PGEs remained unchanged at 4.7 tonnes in 2012.
Western Australia (WA) and the Northern Territory (NT) hold all of Australia's EDR but additional EDR in other States may be established if deposits currently being assessed are confirmed to be viable. However, the EDR of PGEs in individual deposits within State and Territory jurisdictions is often unrecorded, resulting in the overall distribution of the PGE EDR being unknown.
In 2012, Paramarginal Resources increased from 135.3 tonnes to 139.0 tonnes while the Submarginal Resources declined from 35.3 tonnes to 1.4 tonnes in 2012. The Paramarginal Resources are shared mostly between WA (86.3%) and New South Wales (NSW) (13.6%), while the Submarginal Resources are in WA.
Inferred Resources decreased from 148.2 tonnes to 131.0 tonnes in 2012 with WA having most (87.1%) followed by NSW (12.2%).Total Identified Resources of PGEs, which represents EDR plus Paramarginal, Submarginal and Inferred Resources, total about 276 tonnes. Of this amount, deposits that have only PGE resources account for about 51% of the total resources, although all of Australia's production is as a by-product from PGE resources associated with nickel sulphide deposits in WA.
Currently, 400 kilograms (kg) of the published PGE EDR is accessible for mining while the balance of 4.3 tonnes occurs within national parks. The reason for the low Accessible EDR (AEDR) figure for PGEs is that PGE resources are generally not reported by nickel-cobalt producers where PGEs are a by-product of nickel mining.
Currently there are no PGE resources in the AEDR of PGEs which have been reported as Joint Ore Reserve Committee (JORC) Code Reserves. The reason for the absence of published Reserve figure is that companies don't report the PGE content in nickel Reserves.
Expenditure for PGEs is not reported separately and much of the PGE resource is associated with nickel deposits. Areas of activity in 2012 where PGEs were a significant component of exploration targets included regions of the Yilgarn in WA's eastern goldfields, the East Kimberley and West Pilbara as well as the West Musgrave in the border region of WA, the NT and South Australia (SA). Platina Resources Limited was in the process of delineating platinum and scandium resources within their Owendale project in the Fifield area in NSW.
Australia's PGE production (platinum and palladium) in 2012 amounted to 706 kg, which was very minor by world standards . The production was exclusively from nickel sulphide deposits hosted by Archean komatiitic rocks in the Yilgarn Craton of WA.
Based on figures published by the United States Geological Survey and the latest Australian resource figures, world economic resources of PGEs in 2012 remained unchanged at 66 000 tonnes. Australia's share of world EDR was less than 0.1% in 2012. South Africa has most of the world's EDR with 63 000 tonnes (95%), followed by Russia with 1100 tonnes (1.7%) and the USA with 900 tonnes (1.4%).The world's supply of PGEs in 2012 was dominated by South Africa (70% Pt, 36% Pd) and Russia (10% Pt, 41% Pd), with minor contributions from Zimbabwe, Canada, the USA and Colombia.
Platinum Group Elements as the Major commodity
About half of Australia's Identified Resources of PGEs are in the following deposits, which have PGEs as the major commodity.
Munni Munni (WA): Published Measured, Indicated and Inferred Resources of 23.6 million tonnes (Mt) at 1.5 grams per tonne (g/t) Pd, 1.1 g/t Pt, 0.1 g/t Rh, 0.2 g/t gold (Au), 0.09% nickel (Ni), and 0.15% copper (Cu). In its 2012 Annual Report, the owner of the deposit, Platina Resources Ltd, reported that the project was on hold.
Panton (WA): Measured, Indicated and Inferred Resources total 14.3 Mt at 2.19 g/t Pt, 2.39 g/t Pd, 0.31 g/t Au, 0.27% Ni, and 0.07% Cu. On 20 March 2012, Platinum Australia Ltd announced the results of a review of the Panton project, reporting that it would generate a net present value (NPV) on base case assumptions of US$15 million with an initial capital cost of US$172 million. The operating costs was estimated to be US$830 an ounce of Pt+Pd+Au concentrate produced with an average annual production rate of 83 000 oz. On 21 May 2012, Panoramic Resources Ltd announced that it had purchased the Panton PGE deposit from Platinum Australia Ltd. Panoramic reported in its quarterly report for June 2013 that it was in the process of assessing the 2012 bankable feasibility study2.
Fifield (NSW): Platina Resources Ltd3 announced Indicated and Inferred Resources totalling 12.7 Mt at 0.7 g/t Pt for its Owendale North, Cincinnati and Milverton deposits at Fifield. The company also published a scandium (Sc) resource of 10.1 Mt at 340 g/t Sc. Historical production from Fifield amounts to about 640 kg of PGEs. On 11 September 20124, Platina Resources announced results of a scoping study which indicated the economic and technical viability of a combined platinum and scandium mining operation supporting an average mining rate of 6.9 million tonnes per annum (Mtpa) for three years. After three years the scandium-bearing stockpile laterite will continue to be processed to produce:
For the scoping study, capital expenditure was estimated to be $222 million and annual operating costs $62 million for the first three years, reverting to approximately $42 million once platinum processing ceased.
Platina also reported that exploratory drilling in 2013 delineated new zones of fresh rock platinum mineralisation at Cincinatti and Milverton with the highest single platinum assay to date of one metre at 24 g/t Pt from a drill hole depth of 26 metres (Platina Resources Limited, 2013a)5.
Weld Range – Parks Reef (WA): A published Inferred Resource amounted to 14.76 Mt at 1.1 g/t Pt+Pd+Au which occurs in a truncated lateritic profile overlying low-grade primary PGE mineralisation in ultramafic rocks6. The Weld Range PGE deposit is adjacent to the very large Weld Range lateritic nickel-cobalt deposit which has an Inferred Resource of 330 Mt at 0.75% Ni and 0.06% cobalt (Co). An Inferred Resource of 63.5 Mt at 5.2% chromium (Cr), 38% iron (Fe) and 0.38% Ni at a cut-off grade of 4% Cr also occurs within the Weld Range nickel-cobalt deposit. A scoping study was released by Weld Range Metals Ltd (WRM) in August 2010 which concluded that Stage 1 of the project is technically and economically feasible using processing equipment and technology currently used by the steel industry. Dragon Mining noted in its 2012 Annual Report that WRM continued to work with the Wajarri Yamatji people to develop these resources. In 2012, WRM and the Native Title Claimants entering into an Indigenous Land Use Agreement and Mining Agreement to allow exploration, mining and related activities to proceed within and adjacent to the tenements of WRM. The Indigenous Land Use Agreement has been submitted to the National Native Title Tribunal for registration.
Platinum Group Elements as the Minor commodity
PGE resources are present also in deposits where other commodities are dominant, mainly komatiitic nickel-cobalt sulphide deposits as well as lateritic nickel deposits. They include the following deposits.
Rosie (WA): South Boulder Mines Ltd announced an updated total Indicated and Inferred Resource of 1.94 Mt at 1.7% Ni, 0.4% Cu, 0.8 g/t Pt and 1.1 g/t Pd7.
Radio Hill nickel mine (WA): Fox Resources Ltd reported that remaining Indicated and Inferred Resources of palladium amounted to 1.275 Mt at 0.493 g/t. In mid-2010, the company announced updated Indicated and Inferred Resources of 4.22 Mt at 0.65% Ni and 0.76% Cu for its Radio Hill mine. An Indicated and Inferred Resource of 5.78 Mt at 0.54% Ni and 0.67% Cu was reported also for the nearby Sholl B2 deposit, but no details were given for palladium content. The mine is on care and maintenance while the company is investigating options for heap leaching nickel and copper. On 15 November 2011, the company announced it had signed a non-binding Memorandum of Understanding (MOU) with Jiangxi Jiangli Sci-Tech Co. Ltd regarding the development of the Radio Hill and Sholl nickel-copper bacterial heap leaching project in the Pilbara region of WA. On 20 July 2012, Fox Resources reported that the MOU with Jianghi Jiangli had been suspended because of continuing low commodity prices for nickel and copper8.
Waterloo nickel mine (WA): The resources for this deposit were last reported in 2004 as 653 000 tonnes at 2.795% Ni, 0.194% Cu and 0.858 g/t PGE. Recorded production amounts to 185 000 tonnes of ore at 2.76% Ni in 2007 and 57 818 tonnes of ore at 3.085% Ni in 2006, but there are no details on production of PGEs. The mine's owner, OJSC MMC Norilsk Nickel, placed the mine on care and maintenance in November 2008 because of prevailing low nickel prices and reduced world demand at the time.
Nyngan lateritic nickel-cobalt-scandium-platinum deposit (NSW): In its 2004 annual report Jervois Mining Limited reported a resource of 16 Mt at 0.87% Ni and 0.06% Co of which there is 3 Mt at 290 parts per million (ppm) Sc and 0.22 g/t Pt. The scandium-rich portion of this deposit was updated in June 2009 as Measured Resources of 2.718 Mt at 274 ppm Sc and Indicated Resources of 9.294 Mt at 258 ppm Sc.
Horn nickel sulphide deposit (WA): In April 2008, Breakaway Resources Limited reported a small Inferred Resource for Horn nickel deposit of 600 000 tonnes at 1.39% Ni, 0.3% Cu and 0.5 g/t Pd+Pt. In early 2009, the company reported that massive and matrix nickel sulphide mineralisation at the Horn deposit had been drilled over a 500 metre strike length and remained open along strike. Geological mapping undertaken during the March quarter of 2009 confirmed the presence of nickeliferous gossans within a structurally bound, high magnesium oxide (MgO) ultramafic unit immediately south of the known mineralisation. The Revolution prospect9, located immediately north of Breakaway's Horn nickel deposit includes PGE-bearing disseminated nickel mineralisation (12 m at 0.96% Ni, 311 ppm Cu and 424 parts per billion (ppb) Pt+Pd from 192 m and 4 m at 1.14%Ni, 1003 ppm Cu and 749 ppb Pt+Pd from 209 m in drill hole LWDD0809).
Yarawindah Brook (WA): An Inferred Resource of 2.9 Mt at 0.79 g/t PGE was announced by Washington Resources Ltd in March 2006. The deposit was acquired by Northern Minerals Ltd in 2010.
Bamboo Creek tailings (WA): Haoma Mining NL announced on 5 October 2012 that assay results of samples of trial concentrates produced from its recently designed Bamboo Creek pilot plant by the Elazac Process showed they were suitable for commercial extraction of gold and PGEs (platinum and palladium). The company reported that commercial production was planned to commence in the near future. The company reported in its June 2013 quarterly report that test work was continuing to develop a commercial process to extract gold and platinum group metals from both Bamboo Creek Tailings and Mt Webber ores10.
Binti Gossan and Binti South (also known as Emu Lake)(WA): Emu Nickel NL reported in its 2011 Annual Report that a drilling program at Binti Gossan and Binti South had intersected significant nickel, cobalt and PGE values, with some of the best downhole intersections including 0.30 m at 7.55% Ni, 0.35% Co, 1015 ppb Pt and 1726 ppb Pd.
Jack's Hills (WA): Victory Mines Ltd reported on 12 November 201211 that gossan samples collected at the Jack's Hills prospect returned analytical results of up to 13.9% Cu, 87.1 ppm Silver (Ag), 0.77% Ni, 0.24 ppm Au, 1.12 ppm Pt and 1.20 ppm Pd. Historical drill hole samples from a drilling program in 2007 returned values of up to 3.7% Cu, 1.14 g/t Au, 0.48% Ni, 0.73 g/t Pt and 14.4 g/t Ag12.
Other PGE deposits with recorded resources which have had historic interest, but did not record exploration or assessment activity during 2011 include:
Nebo-Babel nickel-copper-PGE deposit (WA): The Nebo-Babel Ni-Cu-PGE deposit discovered by Western Mining Corporation in mid-2000 has a preliminary resource of 393 Mt grading 0.3% Ni, 0.3% Cu and 0.18 g/t PGE. The deposit was later acquired by BHP Billiton Limited as a result of its takeover of Western Mining Corporation in mid-200513.
Syerston lateritic nickel-cobalt-platinum deposit (NSW): In April 2000, Black Range NL announced a total platinum resource of Measured, Indicated and Inferred Resources of 108.3 Mt at 0.21 g/t Pt which occurs partly within the Syerston nickel-cobalt deposit. The platinum resource was calculated using a 0.6% nickel equivalent cut-off grade. In a preliminary prospectus, Ivanplats Limited announced on 10 September 2012 that an internal study in 2005 indicated that, because of increasing capital and operating costs, development of the Syerston deposit was not economically attractive. However, Ivanplats announced that it was monitoring technological advances which could make Syerston commercially viable.
Syerston Project Exploration Licence 7805, drill hole Sy10A (NSW): Exploration Licence 7805 is held by Jervois Mining Ltd which reported analyses from a drill hole in its June 2013 quarterly report14 that revealed up to 2197 ppm Co, 0.35 ppm Pt, 352 ppm Sc 909 ppm vanadium (V) and 42.5% Fe. The company reported that it was planning to commence a 14 hole aircore drilling program to test the occurrence.
Coronation Hill (NT): It was reported in 1990 that the Coronation Hill deposit had an Inferred Resource of 6.69 Mt at 6.42 g/t Au, 1.01 g/t Pd and 0.3 g/t Pt. The deposit occurs within the Kakadu National Park and is inaccessible for mining.
Adamsfield15 (Tasmania): The deposit it is located 70 km west of Hobart within the Franklin-Gordon Wild Rivers National Park. A small near surface Inferred Resource amounts to 14 500 tonnes of ore at 6.5 g/t iridium (Ir), 7.3 g/t osmium (Os) and 0.13 g/t Pt using a cut-off grade of 1 g/t Os+Ir.
Thomson River (Victoria): In 1981, CRA Exploration Pty Ltd estimated resources as 40 000 tonnes averaging 3.2 g/t Pt, 3.6 g/t Pd, 2.7% Cu, 9.5 g/t Ag and 2.5 g/t Au. Intermittent mining since the discovery of the deposit in about 1864 produced around 13 200 tonnes of ore, from which only about 10 kg of platinum was extracted.Coopers Creek dyke prospect, East Walhalla, Maynards Gully (Victoria): Orion Gold NL in its June 2013 report released assay results of samples from a historical drill hole showing 36 metres from a drill hole depth of 303 metres assaying at 1.75% Cu, 0.2% Ni, 0.78 g/t Pt, 1.08 g/t Pd, 0.39 g/t Au and 8.8 g/t Ag. Chip sampling of surface outcrops yielded elevated Cu-Ni-PGE values associated with pyroxenite. The company is planning drilling to test the extent of the mineralisation. Trial geochemical surveys are also being planned to cover Coopers Creek, East Walhalla and Maynards Gully and a trial geophysical survey over Coopers Creek is being designed to develop appropriate methods of exploration for this unique style of mineralisation.