SEG 45 Final_qx4 - Society of Economic Geologists

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26 SEG NEWSLETTER No 53 • APRIL 2003 ... from 25 Exploration Reviews (Continued) EXPLORATION REVIEWS 2002 for the mines in northern Nevada are 506 Mt with an average grade of 0.061 opt Au. Queenstake Resources is purchasing the Jerritt Canyon property from AngloGold and Meridian Gold. Proven and probable reserves are estimated to be about 2.5 Mt with and average grade of 0.236 opt Au, with an additional resource of 4.9 Mt with an average grade of 0.261 opt Au. Of course, exploration potential abounds. WASHINGTON Crown Resources continued to explore the possibility of developing a gold reserve that could be mined underground at the Buckhorn Mountain property (formerly known as Crown Jewell). Several drill holes have intersected grades in excess of 1 opt Au over several feet, within broader zones of greater than 0.1 opt Au. AUSTRALASIA Regional Correspondent: Neil Phillips (SEG 1985) CSIRO, C/- PO Box 3, Central Park, Victoria Australia 3145 E-mail: neil.phillips@csiro.au and Kim Ely CSIRO, C/- PO Box 3, Central Park, Victoria Australia 3145 With contributions from T. Baker (SEG 1994 F), Australia A. Williamson (Department of Mining, Papua New Guinea), PNG P. Grieve, New Zealand AUSTRALIA Australian mineral exploration expenditure for 2002 was US$338 million, remaining at slightly above 17% of the global total, which itself fell last year. As absolute exploration expenditure in Australia has decreased from the peak in 1997, the commodity focus has changed very little. Over half the effort is still directed toward gold, base metals were subordinate, and coal increased from a low base. Mineral sands have been an increasing exploration interest within the Murray Basin of South Australia, Victoria, and New South Wales. By far the greatest overall interest has been in the Archean Yilgarn craton (10% of global total). There is continued interest in some emerging areas, including the Musgrave province, for nickel and copper; the Gawler province, for copper-gold; and the Tanami province and parts of the Kimberley areas, for gold. WESTERN AUSTRALIA In the Yilgarn craton several gold explorers have had promising results from drilling in previously underexplored areas. Independence Gold’s Tropicana project, east of Laverton, has returned significant mineralization from wide-spaced drilling. Two hits 2 km apart returned 9 m @ 1.04 g/t and 4 m @ 1.34 g/t. Cullen Resources has announced results from drilling in the Mt Eureka greenstone belt, which lies 100 km east of the gold-rich Yandal belt. Aircore drilling of the Southern zone prospect has outlined extensive anomalous gold (>100 ppb) in weathered bedrock extending over 1,000 × 400 m with a northeast trend. First pass RC drilling of Southern has returned significant results including 8 m @ 4.28 g/t Au and 38 m @ 1.08 g/t Au. Eureka Northwest is a new discovery made by Cullen when testing a base-of-hardpan gold geochemical anomaly. Three RC holes were drilled to follow up previous RAB and aircore drilling. Hole MERC 55 returned an intersection of 10 m @ 2.52 g/t Au. In the Murchison province, Giralia Resources have announced encouraging results from drilling at their Snake Well gold project. Intersections at the Rabbit Well Calisi prospect of 4 m @ 10.6 g/t Au and 49 m @ 0.55 g/t Au along strike from previous drill intercepts define supergene and primary resource potential associated with zones of quartz veining. Also in the Murchison province, the Mt Gibson gold mine, which has been closed since 1999, may be recommissioned by Oroya Mining, subject to a successful bankable feasibility study. The mineral resource at Mt Gibson stands at 0.75 Moz Au, and following a drilling program designed to convert resources into reserves, it is predicted that the mine could be producing again by late 2003. Following 10 years of legal dispute, the High Court decided on the tenement ownership of the unexplored Bronzewing South lease, on the southern border of Newmont’s 4-Moz Bronzewing deposit. AuDAX Resources has commenced exploration in a JV agreement with Newmont. Rapid definition of RC targets is expected to be generated via an initial RAB/aircore programme of 600 holes covering a corridor south of the Bronzewing mine. Significant results have also been received by AuDAX from the first RC drilling program at the nearby Yandal West prospect, 200 m along strike from the Dragon deposit. Pilbara Mines have reported a resource at the Jaguar base metals deposit of 1.4 Mt @ 3.7% Cu, 13.2% Zn, 0.9% Pb, 140 g/t Ag and 0.18 g/t Au for 184,000 t of contained zinc, 51,800 t of copper and 6.3 Moz of silver. With JV partners Inmet Mining, Pilbara are undertaking further studies with a view toward development of the deposit, located 260 km north of Kalgoorlie. Junior nickel sulfide producer, Mincor Resources, has had recent exploration success in the Kambalda district, including an intersection of 2.5 m @ 6.70% Ni from 422.23 m in massive and matrix style sulfide mineralization. In the southwest Yilgarn at Western Areas’ Forrestonia project, diamond drilling is in progress at the Daybreak prospect, testing for possible extensions to the deposit below a horizontal fault at 400 m depth. Recently announced results include 9.3 m @ 3.5% Ni and 8.8 m @ 2.2% Ni. LionOre received board approval to develop the Maggie Hays nickel deposit, which will be integrated with the nearby Emily Ann operation, resulting in a combined production of 10,000 to 12,000 tonnes (t) of payable nickel per annum. Total Indicated Resource at Maggie Hays is 10.8 Mt at 1.5% Ni. Following the increase of LionOre’s interest in the surrounding Lake Johnson area tenements to 100%, the exploration program for further nickel sulfide deposits will be expanded. LionOre shared more success when Dr. Mark Bennet was recently named Prospector of the Year for his role in the discovery of Emily Ann and the Thunderbox gold deposit. BHP Billiton is expanding its iron ore mining operations near Newman in the Pilbara region, with construction work continuing on plant and railway infrastructure for the Mining Area C project, scheduled to commission in late 2003. The deposit has an estimated resource of 890 Mt, with reserves currently standing at 189 Mt.
APRIL 2003 • No 53 SEG NEWSLETTER 27 A prefeasibility study of Gunson Resources’ Coburn mineral sand project has concluded that the Amy zone deposit, with a resource of 516 Mt averaging 1.4% heavy minerals, will support a profitable, long-term mining operation. Gunson Resources is also actively exploring in the Musgrave Ranges, reporting the intersection of a kimberlitic pipe in the first hole drilled at the Shell Lakes nickel/diamonds project in a program supported by De Beers Australia Exploration. Rio Tinto is commencing a feasibility study on its Argyle diamond mine to determine the potential of the mine’s future as an underground operation. Current mining operations are planned to finish in 2007, but underground development could extend the mine’s life as far as 2020. AKD Limited reported the recovery of diamond indicator minerals from a sampling program at the northern Kimberley region King George project and will be carrying out follow-up sampling. Other diamond exploration activities are occurring in the Seppelt Range, and the South West Diamond JV in the southern Yilgarn region. Pending the outcome of a feasibility study, Platinum Australia is set to open Australia’s first platinum-palladium mine. The Panton Sill deposit in the Kimberley region includes resources of 10.6 Mt @ 5.8 g/t PGE + Au in the Top Reef, and an additional 5.7 Mt @ 3.4 g/t PGE + Au in the Middle Reef system. Commencement of construction later this year could see first production from the new mine in early 2004. The first reconnaissance RC drilling program completed by West Musgrave Mining at its Cavenagh Range project has confirmed the presence of broad zones of copper/PGE mineralization at several prospects. SOUTH AUSTRALIA In the Gawler craton, the latest round of grade control drilling at Dominion Mining’s new Challenger gold mine has confirmed the high-grade nature of the M1 shoot, with results including 5 m @ 224 g/t Au and 8 m @ 20.3 g/t Au. Deeper drilling for the Challenger Underground feasibility study commenced during the quarter, with results from the M1 shoot indicating its continuity at depth. Intersections include 9 m @ 18.85 g/t Au and 5 m @ 27.1 g/t Au. Encouraging results have also been reported from regional RAB drilling in the Challenger corridor. Adelaide Resources are following up on promising diamond drilling results at their Barns gold project with drilling of the untested northern sector of the calcrete geochemical anomaly. Further diamond results from Barns include intersections of 24 m @ 2.19 g/t Au and 11m @ 2.84 g/t Au. Minotaur have continued drilling at the Prominent Hill copper-gold prospect, testing for extensions of known mineralization. Mineralized intervals were intersected in 5 of 7 holes, drilled up to a kilometer from existing mineralization, including 16 m @ 1.39% Cu, 0.10g/t Au and 6 g/t Ag from 321 m. VICTORIA AGD Mining’s recent results at the Augusta gold-antimony deposit at Costerfield support plans for an open cut mine with a 75,000-tonne annual production. Results include 0.15 m @ 86.8 g/t Au and 1.3% Sb from 13.65 m and 0.42 m @ 31.2 g/t Au and 19.9% Sb. The total resource estimate for the project stands at 290,000 t grading 12 g/t Au and 6.2% Sb. A regional aircore drilling program in the Costerfield corridor has produced four additional exploration targets. Ballarat Goldfields has undergone restructure and refinancing, and intends to focus on its objective of establishing a mining operation on its Ballarat tenements, where an inferred resource of around 1 million ounces has been previously calculated. Alliance Energy is set to revive the Maldon gold field (2 Moz historic production) after securing the investment support of Abbotsleigh. Alliance is focussing on several deposits within trucking distance of Roxbury Mining Contractor’s Porcupine Flat treatment plant. Bendigo Mining is undertaking exploration development and bulk sampling work toward development of the New Bendigo gold mine. Recent bulk sampling results returning 3 to 22 g/t have met or exceeded the company’s expectations, and a decision to mine the 700,000 oz resource is scheduled to be made in late 2003. The historic Ararat gold field in western Victoria was a significant source of alluvial gold; however, major primary deposits have never been discovered in the district. Range River Gold has been drilling structural targets within its Ararat project, from which 600,000 oz was recovered from alluvial deposits across the tenement area. Results from the RAB drilling program indicated widespread gold mineralization within volcanogenic and schist rock types considered equivalent to the host rocks at the nearby Stawell gold mine. NEW SOUTH WALES Newcrest is continuing to receive encouraging intersections from near its new Ridgeway copper-gold mine, including 72 m @ 1.78 g/t Au and 0.87% Cu. Drilling at the advanced Cadia East/Cadia Far East project has returned results including 408 m @ 0.70g/t Au and 0.29%Cu. Consolidated Broken Hill drilling results from the Western Mineralisation zone of the Rasp mine silver-lead-zinc project confirm significant high-grade zones and enhance the economic potential of the project. Intersections include 5.3 m @ 18.5% Zn, 13.6% Pb and 60 g/t Ag from 312.4 m and 13.7 m @ 11.7% Zn, 6.6% Pb and 35 g/t Ag from 304 m. QUEENSLAND Buka Minerals has reported encouraging copper grades from the Lady Annie project near the Lady Loretta lead-zinc deposit, Mount Isa inlier. Twenty-nine holes were drilled and results included 35 m @ 3.3% Cu and 19 m @ 5.5% Cu. Elsewhere in the Mount Isa district, Universal Resources announced significant copper-gold intersections at the Lady Clayre prospect, including 40 m @ 1.13% Cu and 0.32 g/t Au, and 12 m @ 6.13% Cu and 4.47 g/t Au. Further drilling by Strategic Minerals at their Woolgar epithermal gold project, in north Queensland has confirmed a 300-m strike length of the Explorer Main Vein structure, still open to the southeast. Recent drilling results include 2 m @ 52.2 g/t Au and 12m @ 8 g/t Au. Further high-grade intersections have also been reported at Newcrest’s Cracow gold project, including 12.15 m @ 13 g/t Au from 561m. MIM Holdings has announced substantial increases to their resources, which is expected to have considerable impact on expansion and mine life of the Mt Isa copper and lead-zinc-silver and Ernest Henry copper-gold operations. The resources include a new 290 Mt open pit resource at Mt Isa, and an underground resource at Ernest Henry of 5 Mt. NORTHERN TERRITORY Elkedra Diamonds has recovered 48 chromite diamond indicators and to page 28 ... EXPLORATION REVIEWS
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SEG 45 Final_qx4 - Society of Economic Geologists

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