TORONTO, ONTARIO -- (Marketwire) -- 12/13/12 -- Orvana Minerals Corp. (TSX: ORV), through its wholly-owned subsidiary, Empresa Minera Paititi ("EMIPA"), provides updated National Instrument ("NI") 43-101-compliant resource and reserve estimates for its Don Mario UMZ copper-gold-silver mine operations in Bolivia. During 2012, EMIPA made significant changes to the mining and processing aspects of the operation thus warranting an update.
The updated NI 43-101-compliant resource and reserve estimates are effective October 1, 2012 and are shown in the tables below. The reserve estimate contains approximately 177,000 ounces of gold, 5.6 million ounces of silver, and 120 million pounds of copper, which is a decrease of about 5%, 2%, and 11%, respectively, after considerations for production through September 30, 2012 as well as the exclusion of certain oxide mineralization whose metals cannot be extracted economically (see press release of January 18, 2012); testing of these ores will continue in order to seek a viable extraction method. The most significant change in the mine plan is the processing of Transition ore by a Flotation-Only process instead of the Leach-Precipitation-Flotation ("LPF") process.
----------------------------------------------- MEASURED INDICATED ----------------------------------------------- tonnes, Gold, Copper, Silver, tonnes, Gold,ORE TYPE '000s g/t % g/t '000s g/t--------------------------------------------------------------------Oxides (in situ) 149 1.90 1.74 77 219 1.94--------------------------------------------------------------------Oxides (stockpile) 757 1.78--------------------------------------------------------------------Transition (in situ) 701 1.30 1.23 44 938 1.22--------------------------------------------------------------------Transition (stockpile) 3 1.40--------------------------------------------------------------------Sulphides 874 1.16 1.15 30 1,344 1.03-------------------------------------------------------------------- 1,724 1.28 1.23 39 3,261 1.32 ----------------------------------------------- TOTAL M&I 4,985 1.31 --------------------------------- ----------------------------------------------- PROVEN PROBABLE ----------------------------------------------- tonnes, Gold, Copper, Silver, tonnes, Gold,ORE TYPE '000s g/t % g/t '000s g/t--------------------------------------------------------------------Oxides (in situ) 131 1.85 1.78 83 196 1.86--------------------------------------------------------------------Oxides (stockpile) 401 1.74--------------------------------------------------------------------Transition (in situ) 643 1.32 1.22 43 908 1.23--------------------------------------------------------------------Transition (stockpile) 3 1.40--------------------------------------------------------------------Sulphides 820 1.13 1.16 30 1,231 1.05-------------------------------------------------------------------- 1,594 1.26 1.23 40 2,739 1.27 ----------------------------------------------- TOTAL 2P 4,333 1.27 --------------------------------- ------------------------------------------------ INDICATED INFERRED ------------------------------------------------ Copper, Silver, tonnes, Gold, Copper, Silver,ORE TYPE % g/t '000s g/t % g/t--------------------------------------------------------------------Oxides (in situ) 1.88 63 38 1.93 1.80 52--------------------------------------------------------------------Oxides (stockpile) 1.79 44--------------------------------------------------------------------Transition (in situ) 1.18 41 97 0.96 1.10 43--------------------------------------------------------------------Transition (stockpile) 1.53 72--------------------------------------------------------------------Sulphides 1.07 31 28 1.02 0.73 17-------------------------------------------------------------------- 1.32 39 162 1.20 1.20 40 ------------------------------------------------ 1.29 39 ----------------- ------------------------------------------------ PROBABLE PROVEN + PROBABLE ------------------------------------------------ Copper, Silver, tonnes, Gold, Copper, Silver,ORE TYPE % g/t '000s g/t % g/t--------------------------------------------------------------------Oxides (in situ) 1.90 67 327 1.85 1.85 73--------------------------------------------------------------------Oxides (stockpile) 1.81 49 401 1.74 1.81 49--------------------------------------------------------------------Transition (in situ) 1.17 41 1,551 1.27 1.19 42--------------------------------------------------------------------Transition (stockpile) 1.53 72 3 1.40 1.53 72--------------------------------------------------------------------Sulphides 1.10 31 2,051 1.08 1.12 31-------------------------------------------------------------------- 1.28 40 4,333 1.27 1.26 40 ------------------------------------------------ 1.26 40 -----------------
