NEWS OUT
Orvana Reports Measured and Indicated Resources Increase of 50% for Pre-Feasibility Study at Copperwood, Michigan, USA
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The resources assume a $2.50/lb copper price, $10/tonne mining cost, $10.80/ton processing cost, 83% copper recovery, $2.75/ton G&A, $5.63/ton sales cost, a minimum of 1.5 metres (5 feet) mining height, and a 0.8% cutoff. Marston & Marston,, Inc., St. Louis, MO, under the supervision of Michael B. Ward, a qualified person who is independent of Orvana for the purposes of NI 43-101, prepared the resource estimate, which effective date is January 25th,2011.
"We will now optimize the throughput for the prefeasibility study since this estimate increased M&I tonnage by over 50% and contained copper by about 40% as compared to that used for the September Preliminary Economic Assessment," said Bill Williams, President of Orvana USA.
Marston & Marston of St. Louis, Missouri was retained to prepare the updated mine plan and design. KD Engineering of Tucson, Arizona will oversee the prefeasibility study.
As reported in the December 14, 2010 press release, the resource estimate of 25.01 million tonnes of 1.40% indicated (771 million pounds) and 36.14 million tonnes of inferred (1,033 million pounds) in the area of Copperwood, referred to as the Copperwood Satellites, will be evaluated after the mine is operating in order to assess expansion possibilities.
Copperwood is a sedimentary stratiform copper deposit hosted by the Precambrian Nonesuch Formation. The mineralized unit, or the copper-bearing sequence ("CBS"), lies at depths between about 30 metres (100 feet) and 265 metres (870 feet). The CBS is amenable to underground, room-and-pillar mining. The mineralization is analogous to the White Pine mine, located 30 kilometres (18 miles) to the east, where nearly 2 million tonnes of copper was produced between 1953 and 1996.
Mineral resources that are not mineral reserves do not have a demonstrated economic viability.
Marston & Marston, under the supervision of Michael B. Ward, who is an independent qualified person for the purposes of NI 43-101, prepared the resource estimate. A summary report will be made available on the Company's website, www.orvana.com, and on SEDAR, www.sedar.com, within 45 days.