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NEWS-CONTINUED tion averaging 94,600 gold equivalent oz/y from open-pit mine production averaging 4.5 million mt/y. Pre-production capital costs for plant and infrastructure plus owner's costs are estimated at $136 million. Cost for an owner-operated mining fleet is estimated at $18.8 million, but no deci- sion has been made as to whether the mine will be owner or contractor operated. Tender documents to invite mining con- tractors working in Mexico to bid on mining at Cerro del Gallo have been drafted and will be issued in coming months. Following that and based upon financing, a decision will be made. Development of the Cerro del Gallo project for gold and silver production requires the processing of three different material types: weathered, oxidized, and sulphide. A 2011 study determined that to fully develop the project for gold and silver recovery, heap leaching should be used for the weathered and oxidized material and CIL should be used for the sulphide mate- rial. The proposed first stage of production is based on heap leach processing of the weathered and oxidized material, which forms the relatively higher-grade gold-silver part of a much larger gold-silver-copper resource at Cerro del Gallo. Endeavor Updates El Cubo Reserves Endeavour Silver reported on July 16, 2012, updated NI 43-101 reserve and resource estimates for its newly acquired El Cubo mine in the southeastern part of the Guanajuato mining district in Guanajuato state, Mexico. Endeavour acquired El Cubo from AuRico Gold in a transaction that closed July 13, 2012. Endeavour also owns and operates the Guanajuato mine in the northwestern part of the Guanajuato mining district, approxi- mately 10 km northwest of El Cubo. The company announced that for greater clari- ty going forward, the Guanajuato mine has been renamed the Bolanitos mine. The updated mineral reserve and resource estimates for El Cubo contain significantly fewer tonnes at significantly higher grades compared to the previous reserve/resource estimate of AuRico, largely due to Endeavour using more con- servative estimation parameters consistent with the reserve/resource estimates for its Bolanitos and Guanacevi mines, En- deavour stated. Substantial mineralized material was reclassified from reserves to resources and from resources to exploration potential as a result of converting a low-grade, open-pit resource at the Dolores-Capulin mineral- ized zone to a higher-grade, underground reserve and resource; removing the Las Torres reserves and resources on the near- by CMT ground because the lease expires next year; and substantially reducing the search radius from known sample data points for the estimation of reserves and resources. Silver proven and probable reserves at El Cubo now total 7.04 million oz. Gold proven and probable reserves total 112,100 oz. Silver measured and indicated resources total 4.43 million oz, and silver inferred resources total 11.41 million oz. The El Cubo property consists of 61 mineral concessions covering 8,144 ha, including several historic and currently active mine adits, ramps, and shafts. Endeavour's new mine plan will focus initially on maintaining the current tonnage throughput at El Cubo of around 1,100 to 1,200 mt/d while progressively increasing the production grades closer to the reserve grades over the next two to four quarters by steadily reducing ore dilution. A new mine manager has been hired, and several new initiatives to reduce dilution and increase grades are under way. www.e-mj.com SEPTEMBER 2012 • E&MJ; 45