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Niobium (Nb) and tantalum often are found together in the same ores, namely columbite ((Fe,Mn)Nb2O6) and tantalite ((Fe,Mn)Ta2O6), as a result of their very similar chemical properties. Niobium is used with iron and other elements in stainless steel alloys. Niobium-titanium alloy wire is used in the medical sector for magnetic resonance imaging. Niobium alloys are strong and are often used in pipeline construction. The metal is used in superalloys for jet engines and heat resistant equipment. At cryogenic temperatures (minus 150 ºC), niobium is a superconductor.
For location of niobium deposits refer to Fig. 14 in the Tin chapter.
Australia's Economic Demonstrated Resources (EDR) of niobium increased by 53% in 2011 to 205 kilotonnes (kt), up from 134 kt in 2010. The bulk of the EDR of niobium is associated with the Toongi deposit, 20 kilometres (km) south of Dubbo in New South Wales (NSW). This deposit is a sub-volcanic intrusive trachyte body (vertical) with dimensions of approximately 900 by 600 metres (m) which has been drilled out to a depth of 55 m to provide a Measured Resource of 35.7 million tonnes (Mt) grading 0.46% Nb2O5, and between 55 and 100 m for an Inferred Resource of 37.5 Mt grading 0.46% Nb2O5.
The other source of niobium EDR is the Brockman-Hastings deposit located 18 km southeast of Halls Creek in Western Australia (WA). This deposit, owned by Augustus Minerals Limited, is hosted by a fine-grained volcaniclastic unit informally known as the Niobium Tuff within a sequence of thick volcano-sedimentary rocks. The Niobium Tuff can be traced over a strike length of 3.5 km and varies in width up to 35 m. The deposit has a Joint Ore Reserve Committee (JORC) Code compliant resource of 36.2 Mt (grading 0.89% ZrO2, 0.36% Nb2O5, 0.018% Ta2O5) comprising an Indicated Resource of 27.1 Mt grading 0.36% Nb2O5 and an Inferred Resource of 9.1 Mt grading 0.36% Nb2O5. These resources are based on a 1500 parts per million (ppm) Nb2O5 cut-off grade.
Paramarginal Resources totalling 82 kt (15 kt in 2010) account for all the Subeconomic Demonstrated Resources. They occur in the Brockman-Hastings (67 kt) in the Halls Creek Orogen and in the Mount Weld (15 kt) deposit in the eastern goldfields in WA.
No changes in the Inferred Resources (418 kt) have been recorded. Western Australia is the largest holder of Inferred Resources with 70% associated with the Mount Weld and the Brockman-Hastings Rare Metal deposits while NSW holds the remaining 30% in the Toongi deposit.
All of Australia's EDR of niobium is accessible.
Joint Ore Reserve Committee (JORC) Code reserves comprise total niobium in Proved and Probable Ore Reserves as defined in the JORC Code. In 2011, reserves of 115kt niobium have been reported. All are contained in the Toongi deposit.
Exploration for niobium is occurring in WA and NSW, but there are no statistics available on exploration expenditure. Drilling by Alkane Resources Ltd at the Railway prospect within Dubbo Zirconia Project has intersected extensive zirconium, niobium, yttrium and rare-earth-element mineralisation. During 2011, Hastings completed a 51-hole drilling program at the Brockman-Hastings deposit and reported numerous significant intersections of ZrO2, niobium and rare-earth elements.
Currently there is no production of niobium in Australia. However, in previous years niobium concentrates were recovered as a by-product of tantalum mining.
Based on incomplete world estimates published by the United States Geological Survey (USGS) for 2011, the largest holders of the world's niobium resources of are Brazil with 2900 kt and Canada with 200 kt. USGS data also estimates that world production of niobium in 2011 was 63 kt, which was a slight increase on 2010 production of 62.9 kt, and was dominated by Brazil with 58 kt and Canada with 4.4 kt.
Historically, Global Advanced Metals (GAM) Pty Ltd (formerly Talison Minerals) Greenbushes mine in WA produced tantalite-columbite concentrate for export. Columbite Fe(Nb,Ta)2O6 is the main niobium ore mineral. The company's primary tantalum plant at Greenbushes has been under care and maintenance since 2008, while its secondary processing plant treats primary tantalum concentrates from the Wodgina mine in the Pilbara region of WA. In January 2011, GAM announced the reopening of operations at the Greenbushes and Wodgina mines.
Galaxy Resources Limited (Galaxy) commenced production from its Mount Cattlin lithium-tantalum mine in December quarter 2010. In December 2010, GAM agreed to purchase 200 000 pounds (about 90 700 kilograms) of contained tantalum pentoxide over the next five years from the Galaxy Resources Mount Cattlin operation. GAM plans to upgrade this material for sale at its Greenbushes operations. When in full production, Galaxy expects to produce 137 000 tonnes per annum (tpa) of spodumene (LiAl(SiO3)2) and 56 000 tpa of tantalite contained concentrate, essentially as a by-product.
Alkane Resources Ltd is in advanced process of developing a Memorandum of Understanding (MOU) with a niobium consumer to form a Joint Venture to produce ferro-niobium from niobium concentrate for specialised alloy markets from the Dubbo Zirconia Project based on the Toongi deposit. In May 2011, the company signed an MOU with a large chemical company to produce around 15 to 20 kt a year of zirconium oxychloride, also using ore from the Toongi deposit.