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REGIONAL NEWS - EXPLORATION ROUNDUP Atacama Pacific Builds Gold Resource at Cerro Maricunga Atacama Pacific Gold, a junior Canadian company headquartered in Toronto, has in- creased the measured and indicated resource at its 100%-owned Cerro Mari- cunga gold project in northern Chile by 65% to 2.68 million oz of gold in 163.9 million mt grading 0.51 g/mt at a 0.3 g/mt gold cut- off, with a further 1.81 million oz in 120.7 million mt grading 0.47 g/mt in the inferred category. The entire resource occurs in oxide-associated gold mineralization. Atacama President and CEO Carl Hansen said, "The large oxide resource and remarkable continuity of the gold mineral- ization combined with excellent metallurgi- cal recoveries ranging from 77% at a 100- mm crush size to 81% at a 19-mm crush suggest that Cerro Maricunga has the potential to be a very attractive develop- ment project. We will proceed with comple- tion of a preliminary economic assessment for a potential heap leach project at a pro- cessing rate of 60,000 to 80,000 mt/d." The Cerro Maricunga resources occur in four zones. The contiguous Lynx and Phoenix zones combine to host the majori- ty of the ounces. Expansion of the Crux zone and discovery of the Pollux zone con- tributed to the growth of the overall resource estimate. Each of the gold zones outcrops on sur- face and remains open to depth, and the Pollux zone remains open to the northwest. A Phase IV exploration program is scheduled to begin at Cerro Maricunga in November 2012 and will include 20,000 to 25,000 m of drilling and a program of bulk metallurgical sampling for bench- plant testwork. The majority of the drill pro- gram will be dedicated to upgrading cur- rent inferred resources. (www.atacamapacificgold.com) Exploration Briefs Iamgold announced an updated, NI 43- 101-compliant resource estimate for its Côté Gold project, located halfway between Timmins and Sudbury in northern Ontario. The company acquired a 92.5% beneficial interest in the project through its acquisition of Trelawney Mining and Exploration on June 21, 2012. The new mineral resource estimate incorporates assay results from an additional 79 holes 22 E&MJ; • NOVEMBER 2012 (44,856 m) since a February 24, 2012, estimate announced by Trelawney. The new Côté Gold resource estimate consists of an indicated resource of 131 million mt averaging 0.84 g/mt gold for 3.56 million oz and an inferred resource of 165 million mt averaging 0.88 g/mt gold for 4.66 million oz. The updated resource estimate, based on a cut-off grade of 0.30 g/mt, represents a 274% increase in indi- cated resources from the previous estimate reported by Trelawney. The updated esti- mate benefited from both infill drilling that substantially upgraded the quality of the estimate through conversion of inferred resources to indicated resources and from step-out drilling to expand the overall resource base. Iamgold's next steps for the Côté Gold project include completion of the 2012 infill drilling program; provision of a resource update based on all validated drill results on hand as of October 1, 2012, as part of the company's annual year-end Mineral Reserves and Resources state- ment; and commencement of a pre-feasi- bility study in the fourth quarter of 2012. (www.iamgold.com) Xstrata Copper has announced a signifi- cant increase to the mineral resource esti- mate at its El Pachón project in San Juan province, Argentina. Total mineral re- sources have increased to 3.3 billion mt at a grade of 0.47% copper, using a cut-off grade of 0.2% copper, and include addi- tional silver and molybdenum by-product credits. This represents a 20% increase from the previous mineral resource esti- mate published in December 2011. Total contained copper metal has increased by 16% to 15 million mt. The new resource estimate for El Pachón is the result of the remodeling of the deposit, including additional drilling from prior drilling campaigns not previous- ly accounted for and the use of new geo- technical, metallurgical, and economic parameters developed as part of the pro- ject's final feasibility studies. El Pachón is a major long-life develop- ment project with the potential to initially produce 400,000 mt/y of copper. (www.xstratacopper.com) Northern Star Resources reports that drilling results from the High-Grade Extension Zone at its Paulsen's underground gold mine in Western Australia indicate a resource grade of about 25 g/mt, compared to a historical mined grade of 8 g/mt from the Paulsens Voyager 1 lode, which is currently the main ore source at the mine. Northern Star has been driving development access to the High-Grade Extension Zone and expects to mine the first production ore from deposit before year-end 2012. The increase in head grade from the High-Grade Extension Zone will underpin a predicted rise in Paulsens production to as much as 115,000 oz in 2013 from about 80,000 oz in 2012. Northern Star also reports that plans are on track to increase Paulsens mine and processing plant capacity to 450,000 mt/y by the end of 2012. (www.nsrltd.com) Oromin Explorations reports that indicated gold resources at the OJVG gold project in eastern Senegal have increased to 3.78 million oz contained in 75.21 million mt grading 1.56 g/mt. Inferred resources cur- rently stand at 960,000 oz in 17.33 mil- lion mt grading 1.73 g/mt. The OJVG deposits are categorized into three groupings: Golouma, Masato and Heap Leach. The Golouma deposits are comprised of three proximal deposits— Golouma, Kerekounda and Kourouloulou— clustered within a 1-km radius of each other and are the highest-grade deposits within the property. Masato is currently the largest single deposit on the property. The heap leach deposits consist of 10 widely-distrib- uted deposits. The Golouma and Masato deposits are providing the basis for a carbon-in-leach feasibility study update, and the Heap Leach deposits are providing the basis for a heap leach preliminary economic assess- ment. Both studies are scheduled for com- pletion before the end of 2012. All of the gold deposits comprising the current resources at the OJVG gold project remain open to expansion both laterally and at depth. Upgrading current inferred gold resources to indicated will be a priori- ty for future exploration efforts. (www.oromin.com) www.e-mj.com