Sandstorm punch #1 SilverCrest Announces Updated Santa Elena Reserves and Resources; Silver and Gold Probable Reserves Increase by 103% and 50%; Silver and Gold Indicated Resources Increase by 127% and 99%
VANCOUVER, BRITISH COLUMBIA--(Marketwired - May 29, 2013) - SilverCrest Mines Inc. (TSX VENTURE:SVL)(NYSE MKT:SVLC) ("SilverCrest" or the "Company") is pleased to announce updated Reserve and Resource estimations for its Santa Elena Mine in Sonora, Mexico. The updated Probable Reserves (underground, open pit and leach pad) are estimated at 8.2 million tonnes grading 74.9 gpt Ag and 1.24 gpt Au containing 19.7 million ounces of silver and 327,430 ounces of gold, representing a 103% increase in contained silver and 50% increase in contained gold over previous Probable Reserves stated below. Updated Indicated Resources (exclusive of Probable Reserves) are estimated at 2.1 million tonnes grading 114.9 gpt Ag and 1.69 gpt Au containing 7.9 million ounce of silver and 116,000 ounces of gold, representing a 127% increase in contained silver and 99% increase in contained gold over previous Indicated Resources stated below. Details of the updated Reserves and Resources are summarized in the following tables and will be included in the Santa Elena Expansion Pre-Feasibility Study (Technical Report) to be filed on SEDAR within 45 days of this release.
J. Scott Drever, President commented: "We are extremely pleased with the results of our updated Reserve and Resource estimates for the underground, open pit and heap leach pad definition and resource expansion drill program. The significant increase in Reserves has clearly defined processing feed for our planned 3,000 tonne per day processing facility (Milling & CCD leaching) for an additional 8 years. What is even more exciting is that we have yet to define the limits of the Main Mineralized Zone and have only begun to explore the newly discovered high grade El Cholugo and El Cholugo Dos zones. We look forward to a banner year in 2014 with the commissioning of the new processing facility in Q1 2014 and the expansion of our annual metals production to an estimated 3.5 to 4.0 million ounces of silver equivalent (55:1 Ag:Au)."
Before production commenced, the Santa Elena open pit defined a mine life of approximately 6.5 years (including ramp up) having a Reserve of 5.1 million tonnes grading 1.72 gpt Au and 73.4 gpt Ag (refer to Technical Report dated April 1, 2011). In April 2011, the open pit Reserve was depleted by approximately 6 months of production and optimized with a remaining 4.79 million tonnes grading 1.81 gpt Au and 75.9 gpt Ag (refer to Technical Report dated April 1, 2011). By January 2012, the open pit was depleted from 2011 production and re-optimized with a resultant Reserve of 3.45 million tonnes grading 1.96 gpt Au and 87.3 gpt Ag showing lesser tonnes and higher grade. Re-optimization of the open pit between April 2011 and April 2013 has reclassified approximately 880,000 tonnes of open pit Reserve to underground Resources which was converted mostly (excluding stope pillars) to the new underground Reserves. The main purpose for re-optimization was to avoid a higher open pit strip ratio at higher cost in future years in the mine life but still be able to mine the displaced Reserves from underground.
SANTA ELENA UPDATED RESERVE AND RESOURCE DATABASES
Based on available data, the current dominant silver-gold mineralization at the Santa Elena Mine is hosted within the Main Mineralized Zone (MMZ) which is a low-sulfidation calcium-rich epithermal deposit that strikes nearly east-west for an estimated distance of 1.3 kilometres with an average true width of approximately 15 metres. The continuous mineralized zone has been drill-tested to a minimum depth of 500 metres from surface and open in most directions. The near-parallel El Cholugo and El Cholugo Dos zones are located approximately 20 to 50 metres below the footwall of the MMZ. These two new discoveries appear to be splays off the MMZ with similar silver-gold mineralization.
The updated underground Reserves and Resources have been independently estimated by EBA, a Tetra Tech Company, utilizing 2012 and 2013 drilling results along with previous independently-validated data (see SEDAR for previous NI 43-101 compliant Technical Reports). Drilling in 2012 and early 2013 was focused on conversion and expansion of underground Resources to Reserves with an average drill hole spacing of approximately 35 metres. Drilling data from 2012 and 2013 used for underground Resource estimate included 138 holes (45,011 metres) and 96 previous holes (14,865 metres). A total of 2,941 composite samples were used as the basis for the block model.
The updated open pit Reserves and Resources have been estimated by SilverCrest utilizing Company extensive production data (blastholes), exploration drilling data and computer modelling. All Indicated Resources in the currently operating open pit have been converted to Reserves as of April 30, 2013.
The Leach Pad Reserves (spent ore) have been estimated by the Company utilizing crusher composite samples, drill data from verification holes on the pad, bottle roll tests to process design specifications and SilverCrest production leach curves. In early May 2013, the Company completed 25 large diameter drill holes (355 metres) on the pad to obtain additional information for the purposes of validation of production data. All spent ore material on the leach pad will be reprocessed through the new processing facility once operational. Only the material currently on the pad and leached (300 day cycle completed or estimated full cycle) has been declared as Reserves. Approximately 750,000 tonnes of open pit material is planned to be placed on the pad during the remainder of 2013 and will undergo only partial leaching before being reprocessed through the new facility. Once this material is placed on the pad and leaching has been discontinued, it will be declared as leach pad Reserves for processing and metal recovery in late 2014 and beyond.
Extensive metallurgical test work including ongoing operations data show that all declared Reserves are amenable to conventional leaching either by heap leach technology or standard CCD milling with a Merrill Crowe recovery system for dore bar production. Estimated recovery grades are stated below in Reserves Criteria table.