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ShafterLocation and HistoryThe Shafter silver mine is located in Presidio County, southwest Texas, and is fully accessible via paved highway from El Paso, Texas. Silver was mined in the Shafter region from 1883 until 1942, when the mine was closed, not by lack of ore, but by the War Act. Total production during that period was 2.3 million tons of ore containing 35 million ounces of silver at an average grade of 15.24 ounces per ton. In 1977 Gold Fields Mining Company acquired and held the project until 1994, during which time over $20 million was spent on project development. Beginning in 1977 a systematic surface-drilling program of 262,400 feet in 891 drill holes resulted in the discovery of the eastern extension of the Presidio deposit, extending along strike for more than 5,000 feet from the lowest development work in the Presidio mine. Further development was halted due to the decline of the silver price at that time. In 1994 the project was acquired by the Rio Grande Mining Company and additional exploration, mine planning, metallurgical design and studies were carried out. Silver Standard Resources subsequently acquired Rio Grande in 2001. In 2003 Silver Standard relocated a 900 ton per day mill to site. Aurcana acquired the Shafter silver mine in 2008. All necessary infrastructure is in place with a major power line and paved highway crossing the property, an electrical sub-station on site, a 1,050 foot shaft serviced by a 80 ton per hour hoist, and 5,100 feet of underground development. Production The 100% owned Shafter mine is planned for silver production start up at 3.2 million ounces per year. The mine contains an estimated measured and indicated resource of 24,600,000 ounces of silver and an inferred resource of 22,800,000 ounces of silver. Aurcana has fully committed its proven construction and operating team to commence operations at the Shafter mine. With a relatively low capital cost, the Shafter mine represents a low-risk project. Due to the advanced stage of development at site, the project can be rapidly moved to production. The deposit and contained resources are well identified and quantified. Metallurgical testing indicates that a high recovery is probable. "This is a unique and timely opportunity for Aurcana and its shareholders. The acquisition of the pure silver Shafter mine has transformed Aurcana into a primary silver producer." Ken Booth, President The Resource 24.6 million oz @ 8.48 oz per ton -- Measured and Indicated 22.8 million oz @ 10.52 oz per ton -- Inferred The Production Start up at 3.2 million oz per year Over ten year mine life Silver doré bars poured on site The Opportunity Short term to production Proven operating team in place Key infrastructure on site Geology and Metallurgy The Shafter deposit is the northeastern, down-dip extension of the previously mined Presidio mine workings and has been divided along its east-west trend into five exploration sectors or blocks. Silver mineralization at Shafter and the historical Presidio mine is hosted by the Mina Grande Formation limestone over an approximate three mile length. It is classified as a carbonate replacement deposit (CRD) and is similar to many of the world's largest CRDs which occur in adjacent northern Mexico. Considerable test work done by previous operators indicates the highest recoveries for silver will be by in-tank leaching followed by production of a silver doré using the Merrill Crowe process. Historical silver recoveries at the Presidio mine were 86% to 87% and are expected to be similar at Shafter. Resources Shafter 43-101 Report Tetra Tech prepared a NI 43-101 compliant Technical Report and developed a three-dimensional computerized model of the Shafter silver deposit that was used in the development of the resource estimate. The previous mining companies' results tend to match the historical mining records. The sample database is representative of the tenor of the mineralization and industry standard procedures were followed including determination of the precious metal grades by standard fire assaying techniques. The project contains a resource of 47.4 million ounces.
Exploration Past production from the Shafter to Red Hills mineral trend has included high-grade silver, lead and zinc. The district offers good potential for additional production of silver, copper, lead, zinc and gold. There are several other exploration targets on the property, both gold and silver. An integrated program of geologic mapping, geochemical sampling, geophysical testing and exploration drilling is being planned. |
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