PR, 11/15/07, Ayelen Vein Resource estimate, porphyry style mineralization.
Esperanza Silver Corporation: San Luis' Initial Resource Estimate; Nearby Porphyry-Style Base-Metal Discovery
Thursday November 15, 9:30 pm ET
VANCOUVER, BRITISH COLUMBIA--(Marketwire - Nov. 15, 2007) - Silver Standard Resources Inc. (NASDAQ:SSRI - News; TSX:SSO - News) and Esperanza Silver Corporation (TSX VENTURE:EPZ - News; PINK SHEETS:ESPZF - News) today reported that Silver Standard has delivered an initial resource estimate for the Ayelen Vein on the companies' joint venture property in Peru. Ayelen is one of numerous veins found to date on the property.
In addition, the companies report the discovery of significant porphyry-style base metal mineralization six kilometers southeast of the Ayelen Vein.
Ayelen Vein Resource Summary - November 2007
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Silver Gold Gold-
Silver Gold Grade Grade Contained Contained Equiv-
Grade Grade (oz/ (oz/ Gold Silver alent
Category Tonnes (g/t) (g/t) ton) ton) (ounces) (ounces) (ounces)
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Measured 41,400 483.4 21.57 14.1 0.63 28,700 643,000 42,000
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Indicated 632,500 318.8 11.63 9.3 0.34 236,500 6,483,000 366,000
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Measured
and 673,900 328.9 12.24 9.6 0.36 265,200 7,126,000 408,000
Indicated
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Inferred 14,600 282.4 9.33 8.2 0.27 4,400 132,000 7,000
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Gold-equivalent ounces assume a 50:1 silver-to-gold price ratio.
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Resources were estimated in a block model (3 meter by 3 meter by 3 meter) and tabulated using an inverse distance squared algorithm with a silver cut-off grade of 40 grams per tonne. The database contained 900 individual samples which were combined into 876 one-meter composites. It was prepared by Doug Blanchflower, P.Geo., an independent qualified person, as defined by Canada's National Instrument 43-101.
Underground Exploration Program Being Permitted
Silver Standard, as joint venture operator, is in the final stages of preparing an application for permits to begin an underground exploration program targeting the Ayelen Vein, including further drilling. This underground work will determine the continuity of precious metal mineralization and form the basis of an updated resource and feasibility study.
Exploring for Other High-Grade Structures
Exploration continues on other known quartz veins in the vicinity of Ayelen to identify additional highgrade structures. This work will consist of prospecting, geological mapping and geophysical studies followed by drilling. Recent field work has identified several other vein structures on the 25,000-hectare property. These will be systematically sampled and, if warranted, drilled in the coming field campaign starting in 2008.
Early Feasibility Study Planned
Silver Standard has announced that a feasibility study for the development of Ayelen is expected to begin in early 2008. Preliminary metallurgical test work using conventional hydrometallurgical processing has yielded recoveries of 90% for gold and 80% for silver. Additional studies are underway to optimize recovery rates.
BP Zone - A New Base Metal Discovery
As a result of ongoing property-wide exploration, the joint venture earlier this year identified a large alteration zone covering 12 square kilometers, now called the BP Zone. This area lies approximately six kilometers southeast of the Ayelen Vein (see attached map). It is contained within the joint venture property and represents a separate area of mineralization distinct from the Ayelen area of known epithermal vein mineralization.
The BP Zone was originally recognized through alteration mapping and stream sediment geochemistry. A follow-up program identified large areas where surface grab samples yielded significant base metal (up to 2.2% copper and 11% zinc) and precious metal anomalies. The program was followed by a detailed geophysical study over the area which yielded numerous other anomalies.
The area is characterized by mineralized hydrothermal breccias with identified outcrop dimensions of approximately 250 by 450 meters. The breccia contains pervasively altered fragments of volcanic rock with a sulfide bearing matrix. The rock chip sampling determined areas of distinct, yet overlapping, copper, zinc and lead mineralization within this zone. Anomalous silver and gold was also found.
Drilling Encounters Porphyry-Style Mineralization
At the end of this year's drill program, four diamond drill holes tested a number of geophysical anomalies that are coincident with the BP Zone. Noteworthy results include:
Drill hole SL-131 was drilled within the outcrop area of hydrothermal breccia and from surface encountered 45 meters containing 0.53% copper, 62.7 grams per tonne silver, 0.02 grams per tonne gold, 0.11% lead and 0.10% zinc.
Drill hole SL-130 was drilled approximately 300 meters northwest of the outcropping breccias and was designed to test a geophysical anomaly. This hole encountered a 54-meter section of hydrothermal breccia containing 0.11% copper and anomalous silver, gold, lead and zinc. This intersection possibly expands the area of the known mineralized breccia or indicates the presence of multiple breccia bodies.
Drill holes SL-132 and SL-133 were drilled west and southwest respectively of the outcropping breccia and were designed to test additional geophysical anomalies. Although there was porphyry-style alteration they did not yield significant metal values.
Aggressive Drill Program in 2008
Extensive rock alteration and the hydrothermal breccias, as found both at surface and in the drill holes in the BP Zone, are indicative of a porphyry-style environment and potential associated mineralization. Silver Standard is finalizing drill permits to allow full access to the BP Zone and is planning an aggressive drill campaign on completion of permitting. |
