Engineering and Mining Journal - Whether the market is copper, gold, nickel, iron ore, lead/zinc, PGM, diamonds or other commodities, E&MJ takes the lead in projecting trends, following development and reporting on the most efficient operating pr
Issue link: https://emj.epubxp.com/i/109221
REGIONAL NEWS - EXPLORATION ROUNDUP Ivanplats Expands Kamoa Resources Ivanplats reports that a new, independent review of drilling results at its Kamoa copper project in the Democratic Republic of Congo has more than doubled the project's estimated indicated mineral resources. The estimate increases Kamoa's indicated resources to 739 million mt grading 2.67% copper, containing 43.5 billion lb of copper, an increase of 115% over the previous September 2011 estimate. Both estimates used a 1% copper cut-off grade and a minimum vertical mining thickness of 3 m. The review was conducted by AMEC E&C; Services of Reno, Nevada, and was based on core from 555 holes drilled to December 10, 2012. At a higher, 2% copper cut-off grade, Kamoa's indicated resources now total 550 million mt grading 3.04% copper, containing 36.9 billion lb of copper. Ivanplats intends to use the new resource estimate as the basis for an updated PEA that is expected to be released in the first half of 2013. The Kamoa deposit lies under cover and does not outcrop. The true thickness of the copper mineralization varies from 2.4 m to 17.6 m at the 1% copper cut-off. The deposit is relatively flat lying, dipping generally west to east at between 0° and 20°, and at its deepest has been intersected at more than 1,500 m below surface. Highgrade bornite-chalcocite mineralization remains open down-dip to the east and along strike to the south. The Kamoa project is located in the Kolwezi district of Katanga province, approximately 25 km west of the town of Kolwezi. The copper mineralization identified at Kamoa is typical of sediment-hosted stratiform copper deposits. A regional exploration program is ongoing, with drilling planned at prospective targets on the more than 9,000 km2 of exploration tenements held by Ivanplats in a variety of geological settings within Katanga province. (www.ivanplats.com) Exploration Briefs OZ Minerals has reported an updated mineral resource for its Carrapateena coppergold-silver-uranium deposit in South Australia, showing a 43% increase in total indicated and inferred resources at a 0.7% copper cut-off from its previous 2011 estimate. Combined indicated and inferred resources at Carrapateena now 22 E&MJ; • FEBRUARY 2013 total 292 million mt grading 1.29% copper, 0.48 g/mt gold, 5.4 g/mt silver, and 207 ppm uranium. The updated Carrapateena resource is based on data from 93 drill holes, including wedges, totaling 57,257 m that intersected the main body of the copper mineralization. OZ has also reported a new mineral discovery at its Khamsin prospect 10 km northwest of Carrapateena. The first Khamsin drill hole returned an intersection of 440.6 m grading 0.43% copper and 0.08 g/mt gold from 1,005.4 m, including 26.7 m grading 1.48% copper and 0.13 g/mt gold from 1,005.4 m. The Khamsin alteration and mineralization style are analogous to rock types intersected on the margins of the Carrapateena deposit. Within the Carrapateena licenses, OZ has identified nine priority gravity and coincident magnetic targets that will be subject to further evaluation. (www.ozminerals.com) Duluth Metals has reported expanded resources at the Twin Metals joint venture in northern Minnesota, owned 60% by Duluth Metals and 40% by Antofagasta plc. A new NI 43-101 technical report completed by AMEC E&C; Services confirms resources in the project's copper-nickelplatinum group metals polymetallic sulphide deposits as being among the world's largest, with contained metals, using a 0.3% copper cut-off, of 13.6 billion lb of copper, 4.4 billion lb of nickel, and 21.4 million oz of palladium+platinum+gold indicated and 11.9 billion lb of copper, 4.1 billion lb of nickel, and 12.8 million oz of palladium+platinum+gold inferred, representing an average 19% increase from a June 2012 interim AMEC report. The resources occur in three deposits: Birch Lake, Maturi and Spruce Road. The S3 sub-unit of the Maturi deposit, using a higher 0.5% copper cut-off, contains 622 million st indicated and 198 million st inferred, which may have potential to provide higher-grade mill feed for the early stages of any planned mining operation. (www.duluthmetals.com) Northern Star Resources has signed a farm-in and joint venture agreement with Fortescue Metals to earn up to a 60% joint-venture interest in the non-iron ore rights to key Fortescue tenements around and between Northern Star's Paulsens and Ashburton gold projects in Western Australia. Northern Star will pay A$2 million up front for an immediate 25% jointventure interest, with the right to earn another 35% by spending a further A$4 million within two years. After Northern Star's initial 60% earn-in, Fortescue must co-contribute or dilute to an eventual 2% net smelter royalty. The Northern Star/Fortescue deal covers more than 400 km of strike along two highly prospective parallel structural corridors. The northern structure, the Nanjilgardy fault, hosts the Paulsens gold mine and Ashburton's 1-million-oz Mt Olympus deposit, along with other prospective targets. The southern structure, the Baring Downs fault, is considered to be a geological replica of the Nanjilgardy fault but has had virtually no exploration. Northern Star plans to target both structures as part of an A$20 million "exploration blitz" during 2013. (www.nsrltd.com) Nuinsco Resources reports that analytical results from drill holes on the Berta copper project in northeastern Turkey continue to indicate significant scale for the Berta porphyry mineralization. The work program was operated by Nuinsco's joint-venture partner Xstrata Copper. A total of six diamond drill holes were completed during the autumn of 2012, following-up on the widespread and very anomalous copper mineralization identified in previous work programs. The drilling targeted areas not previously drilled but which are overlain by very strong copper-insoil anomalies located at the center, east, and north of the Berta porphyry system. The total area covered by 17 widelyspaced drill holes completed to date is about 8 km2. Copper has been obtained in all holes, but the east side of the Berta complex seems to provide better overall results. Recently reported drill hole SD-12-14 of the 4,720-m 2012 program returned 488.4 m grading 0.06% copper, with grades up to 0.45% copper over 1.5 m. One km to the southeast, DDH SD-12-15 returned 876.4 m of 0.06% copper, including grades up to 3.76% copper over 0.2 m. (www.nuinsco.ca) www.e-mj.com