Prefeasibility Study Update on Lindero Oxide Gold Deposit

 

 

VANCOUVER - Mansfield Minerals Inc. reported a prefeasibility study update on the Lindero heap leach oxide gold deposit, Salta Province, Argentina. AMEC Americas Limited is over-seeing completion of this study with a delivery date currently projected in late Q4 2009. The Lindero gold deposit hosts an NI 43-101 compliant measured and indicated oxide gold resource of 70.3 MT grading 0.72 grams/tonne containing 1.6 million oz gold. There is an additional 270,000 oz gold at 0.61 grams/tonne in the inferred category (Golder Associates, 2008). The afore-mentioned resources are calculated at a cut-off grade of 0.45 grams/tonne gold.

The AMEC prefeasibility study is presently modeling an open-pit heap-leach operation which suggests a mining rate (total material moved) ranging from 12 to 22 million tonnes per annum, delivering 7 to 9 million tonnes per year to the leach pad at strip ratios in the 1.0 to 1.3 to 1 range. The above projections are based upon the project metrics that are presently known, however the Company cautions that the mineral resources are not mineral reserves and have not been demonstrated to be economically viable.

Metallurgical studies are ongoing at Kappes Cassiday & Associates in Reno, Nevada, under the supervision of American Au Ag Associates. A high pressure grinding roll system appears to be the appropriate crushing system to optimize costs, recoveries, and project economics. Heap leach oxide gold recovery is estimated at 70%+. The Lindero gold deposit carries an average copper grade in the range of 0.10%. Leach tests by Kappes Cassiday show a copper content in leach solution of 153.3 ppm, well below the threshold at which the copper content could be of concern with respect to the gold recovery and cyanide consumption. The Company does not plan on recovering copper.

The company’s address is Suite 922, 510 West Hastings Street, Vancouver, BC V6B 1L8, (604) 681-4462, fax: (604) 681-0180, email: [email protected].