The Rossi/Storm project is a joint venture (40% Yamana) with Barrick Gold Exploration Inc. (60%). Barrick is the operator of the mining operations.
OVERVIEW
Location
Property spans 28 kilometers on the northern end of the Carlin Trend, Nevada, USA.
Type of operation
100% of the ore is mined from underground operations using drift and fill method. The ore is processed at near-by Barrick treatment facilities (both autoclaving and roasting).
Proven and Probable Reserves (40% share)
209,000 tonnes at 14.36 grams per tonne = 97,000 gold equivalent ounces
Inferred Resources
224,000 tonnes at 10.1 grams per tonne gold = 72,000 gold equivalent ounces
Expected Annual Metal Production
30,000 - 40,000 equivalent gold ounces for both 2008 and 2009
Geologic History
The STORM resource is a high-grade, structurally controlled refractory gold deposit occurring at depths of 200 to 650 meters. It is hosted primarily by silty carbonate and carbonate breccia bodies within the Devonian Popovich Formation. The local geology consists of chert , siltstone and mudstone of the Vinini Formation in thrust contact with limestone, calcareous mudstone, carbonate breccia, dolomite and carbonaceous mudstone.
Intruding the sedimentary sequence are Jurassic to Tertiary age dikes and sills occurring predominantly as north to northwest trending dikes and dike swarms, with occasional silling along low angle structures and contacts. These high-angle north to northwest structures acted as conduits for mineralizing fluids.
Silicification and pyritization are the dominant alteration types associated with gold mineralization.
Collapse breccia bodies, found within the STORM resource, are interpreted as products of decarbonatization and resultant volume loss of underlying limestone. Collapse brecciation occurred prior to, during and following gold deposition. Although collapse breccias occasionally are hosts to ore-grade gold mineralization, and high-grade clasts are often found in the breccia bodies, more typically gold is lower grade and disseminated throughout the breccia. Higher grade gold (+ 6.8 g/t) associated with fine-grained arsenical pyrite is generally confined to the common footwall of intersecting structures within favorable horizons of the Popovich Formation.
In 1998 Meridian entered into a mining agreement after Barrick completed their earn-in requirement with Meridian holding a non-operating 40% of the venture. A cooperative mining agreement is in place between Meridian, Barrick and Gold Corp and an ore sale agreement in place between Meridian and Barrick for Meridian's interest. Commercial production began in April of 2007.
Exploration upside includes extension of the Discovery Zone down dip and to the north; potential connection of the End and Discovery Zones; and from new deposits discovered from either underground or surface exploration.