australia's identified mineral resources 2004 - Geoscience Australia

More documents

Recommendations

Info

AUSTRALIA’S IDENTIFIED MINERAL RESOURCES 2004 Resources EDR for gem/near gem was 72.2 Mc and industrial 75.1 Mc, both up 7% compared with 2002 as a result of reassessment of resources at the Argyle mine. Accessible EDR All diamond EDR is accessible for mining. JORC Reserves JORC Code reserves account for almost all AEDR. The remaining AEDR comprise those measured and indicated resources (reported by mining companies), which Geoscience Australia has assessed as being economic in the long term. Exploration ABS data indicate that expenditure on exploration for diamond in Australia in 2003 was $27.6 million, down 15% on 2002. Exploration was concentrated in Western Australia, notably the Kimberley region, Northern Territory and South Australia. Airborne gravity surveys flown by Gravity Capital in the Kimberley region identified new targets at Ellendale (20 targets) for Kimberley Diamond Co, at North King George (9) for Striker Resources and AKD Limited, and Phillips Range (38) for Thunderella Exploration. Follow-up drilling at Ellendale in 2003 identified two new pipes and an alluvial palaeo-channel. Seppelt (WA): Striker Resources NL reported bulk sampling of its Seppelt 2 pipe in the North Kimberley region had indicated a grade of about 2 cpt with gem quality diamonds up to 8.5 carats in size. Initial micro diamond results for the Seppelt 5 pipe are consistent with Seppelt 2. A zone of high-grade kimberlite at Seppelt now extends over 3 km in length, encompassing both the Seppelt 2 and Seppelt 5 kimberlite occurrences which are 2.5 km apart. A sample of 3566 carats from Seppelt 2 was valued at US$48 per carat using a +1.5mm lower screen cut-off, and around US$35 per carat using a 1 mm cut-off. Timber Creek (NT): Tawana Resources has so far found 660 carats, however reliable values cannot be assigned to diamonds from valuation parcels of less than 2000 carats. A coating around the diamonds has delayed recovery and a ‘diatech’ detection method is being trialled. To date, this method has been more successful than x-ray methods for detecting diamonds, and in addition, has detected yellow diamonds not previously recovered by either grease tables or x-rays. Other areas of diamond exploration in 2003 included: the Altjawarra Craton NT (Elkedra Diamonds); the Pilbara region WA; and Copeton NSW (Cluff Resources Pacific). 30 Production Australia produced 31 Mc of diamond in 2003, making it the world’s largest producer of diamond by weight. Australia is the largest producer of industrial grade diamond and the second largest producer of gem/near gem diamond. Botswana, a close second in terms of diamond production by weight, is the leading diamond producer by value with Australia ranked eigth. Nearly all production was from the Argyle mine in the Kimberley region of Western Australia, which produced 30.9 Mc of mostly industrial and cheap gem quality diamonds. Argyle production was down nearly 8% on 2002 production and reflected the mining of lower grade material in the Northern Bowl and the cessation of mining of alluvial diamonds in late 2002. A total of 9787 t of ore was mined from the Argyle AK1 pipe with an average grade of 3.16 cpt, comparable with 2002 figures (3.19 cpt). At Ellendale in the West Kimberley region, 57 000 carats were produced in 2003 with the top several metres of the Ellendale 9 pipe yielding high-value fancy yellow gem diamonds. Recent large diameter drilling and sampling has upgraded the resource at Ellendale 9, 4 and the satellite pipe to 90 Mt at 6.2 carats per hundred tonnes.
AUSTRALIA’S IDENTIFIED MINERAL RESOURCES 2004 At Merlin in the Northern Territory, a total of 62 000 carats was mined in 2003. World Ranking Australia’s EDR of industrial diamond ranks third (16% of current world total EDR), after the Congo (Kinshasa) and Botswana (26% and 23% respectively). Detailed data are not available on world resources of gem/near gem diamond but Australia has one of the largest stocks for this category. Industry Developments Argyle (WA): A 2.2 km exploratory decline to 300 m depth is being developed to test the fragmentation and ‘caveability’ of the ore body below the open pit as part of a full feasibility study (costing $70 million) to assess the viability of underground mining after the open pit reserves are exhausted in 2008. A decision on the underground mine development option is expected in 2005. Merlin (NT): Mining ceased in the second quarter of 2003 ending five years of operations. A total of 468 000 carats was produced at Merlin, mostly from the four southern pipes – Excalibur, Launfal, Palomides and Sacramore. The diamonds were mostly of gem quality with an average value of US$100 per carat and included the largest diamond found to date in Australia, a 104.73 carats gem named Jungiila Bunajina after the traditional owners of the region. Following an unsuccessful tendering process to sell the Merlin deposit, Rio Tinto Ltd closed and rehabilitated the mine in the second half of 2003. In September 2003, Striker Resources acquired the exploration tenements around the Merlin mine in an arrangement that includes access to Rio’s Kimberley diamond database. Ellendale (WA): Kimberley Diamond Company Ltd reported that production from Pipe 9 continued to yield diamonds of very high quality with some sales in excess of US$200 per carat. Production is scheduled to increase in the second half of 2004 with the commissioning of a larger (2.2 Mtpa) plant. Long term intentions are to increase to 8.8 Mtpa producing 400 000 carats per annum by 2006 making it one of the world’s five largest producers. Seppelt (WA): A pilot HMS treatment facility was deployed at the Seppelt 2 site late in 2003 to treat a trial sample of approximately 20 000 t of near surface kimberlite and infill material at a rate of up to 30 t/hour. The trial is expected to recover in excess of 15 000 carats of diamonds totalling around $1 million in value. It will provide mineral processing information and run-of-mine diamond value that will be input to the decision on the possible development of an open-pit operation. The pit would exploit the high-grade 2 cpt weathered kimberlite, which underlies the lower grade infill gravels. Gold Gold has a range of uses but the two principal applications are as an investment instrument and in the manufacture of jewellery. Secondary uses, in terms of the amount of gold consumed, are in electronic and dental applications. Gold prices maintained the higher levels attained in 2002 through much of 2003 before a further increase over the last few months resulted in the year-end price exceeding US$400/oz. The continuing stronger price contributed to an increase in spending on exploration for gold. Increased gold output in 2003 arrested the downward trend that started after the record production in 1997. In 2003 gold contributed over $5.5 billion to the Australian economy in export earnings. 31 Resources Australia’s gold resources occur and are mined in all States and the Northern Territory. In 2003 EDR, which fell by 33 t (1 Moz), accounted for 78% of total demonstrated resources. EDR increased in Queensland, New South Wales, Victoria and South Australia. Western Australia’s EDR, which is almost 62% of the national total, fell by 47 t (1.4%) to 3287 t in 2003. South Australia had the second largest EDR. In the Northern Territory, EDR fell by 42 t to 180 t. Only minor variations were recorded in the other States.
Page 1 and 2: AUSTRALIA’S IDENTIFIED MINERAL RE
Page 17 and 18: COMMODITY REVIEWS Construction of t
Page 29: AUSTRALIA’S IDENTIFIED MINERAL RE
Page 71 and 72: Pouring copper anodes, Olympic Dam
Page 81 and 82:
AUSTRALIA’S IDENTIFIED MINERAL RE
Page 83 and 84:
Page 85 and 86:
show all

australia's identified mineral resources 2004 - Geoscience Australia

Create successful ePaper yourself

Delete template?

Save as template?