Assay results from 37 holes drilled on roughly 80-to-100-metre centres point to an indicated resource of 63.6 million tonnes grading 101 grams silver per tonne (2.9 oz. per ton) and 1.76% lead, equivalent to 207 million oz. silver and 1.1 million tonnes lead. The estimate, provided by Snowdon Mining Industry Consultants, is based on a cutoff grade of 50 grams silver-equivalent.
An additional 16.9 million tonnes grading 67 grams silver per tonne (1.9 oz. per ton) and 0.3% lead, equivalent to 36 million oz. silver and 56,776 tonnes lead, is inferred.
More than half the contained silver in the indicated category occurs in a central, near-surface, higher-grade core of 13.2 million tonnes grading 277 grams (8.1 oz.) silver and 3.76% lead, equivalent to 117 million oz. silver and 495,000 tonnes lead. In addition to the silver and lead, minor amounts of zinc and copper are present.
At a higher cutoff grade of 100 grams silver-equivalent, the contained silver drops marginally to 186 million oz. in the indicated portion, for an estimated 38.8 million tonnes grading 149 grams (4.3 oz.) silver and 2.4% lead. Given the size and near-surface distribution of mineralization, Galena Hill would appear to have potential as an open-pit target.
Drilling has outlined a generally flat-lying zone of replacement-style galena matrix breccia mineralization in a latitic volcanic rock sequence. The mineralized zone ranges from 115 metres at its thickest to less than 10 metres along its boundaries. The area of mineralization averaging greater than 50 grams silver measures about 400 by 500 metres. The top of the mineralized body is exposed at surface in some areas but can be covered by as much as 40 metres of sedimentary cap rock in other areas. The mineralized body is bowl-shaped, with the flat side up and the thickest part in the middle, tapering toward the edges.
Hatch Consultants is performing preliminary metallurgical tests, using flotation methods, on four composite drill samples. Petrographic work by Panterra Geoservices on Galena Hill drill core samples detected no oxidation or oxide minerals. The main “ore” minerals identified were galena, pyrite, sphalerite and chalcopyrite (in order of declining abundance). No discrete silver minerals were observed.
The Navidad project centres on a 6-km-long, northwest-oriented series of hills individually referred to as Calcite, Navidad, Galena and Barite. Replacement-style mineralization has been traced on surface across the Navidad, Galena and Barite hills for 3 km. Soil sampling over a gridded area 6 km long by 1 km wide has outlined a series of coinciding silver, lead and copper anomalies over each of the hills, including Calcite Hill, 1 km or more northwest of Navidad Hill, in an area that has seen limited prospecting.
IMA completed 53 core holes totalling 8,853 metres during the first phase of drilling between the end of November 2003 and early March 2004. In addition to Galena Hill, IMA tested a series of near-vertical bonanza-grade structures (up to 50,520 grams or 1,475 oz. silver) on Navidad Hill with eight closely spaced holes. These holes, which tested only 80 metres of the 475-metre mineralized strike length, intersected promising values.
The 800-metre-long corridor between Galena and Navidad was tested with five widely spaced holes. Three of these holes intercepted what IMA is calling the Connector zone. IMA also sunk one wildcat hole into a parallel linear structure called the Esperanza trend, across the valley on the southwestern side.
IMA intends to follow up on these other targets with an 8,000-to-10,000-metre second round of drilling.
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