The June 30 JORC-compliant mineral resource and ore reserve statement for G-Resources Group’s Martabe Gold-Silver Project has resulted in a significant increase in confidence in Purnama and Barani resource categories. This follows further in-fill drilling at both locations.
The statement, which incorporates post-mining depletion, has also resulted in marginal changes in gold and silver ounces.
The total G-Resources’ JORC-compliant mineral resources as at June 30, 2013, are 206.6 million tonnes @ 1.2 grams/tonne gold and 11 grams/tonne silver, for 8.2 million gold ounces and 75.3 million silver ounces. This is an increase in gold resources of 150,000 ounces and a decrease of 1.7 million ounces of silver.
The total JORC-compliant ore reserves as at June 30 are 51.4 million tonnes @ 1.9 grams/tonne gold and 20.2 grams/tonne silver for 3.2 million gold ounces and 33.4 million silver ounces - an increase in gold reserves of 140,000 ounces and a decrease of 299,000 silver ounces.
The standout contributor to the gain in reserves, despite depletion, is the impact of the additional mineral resources at Purnama which were identified by drilling. The waste-to-ore strip ratio at Purnama has also reduced from 1.4 to 1, to 0.8 to 1, which over the mine life will result in further cost efficiencies in mining.
The Purnama and Purnama Timur deposits have also been combined into the one mineral resource. Additional drilling and more advanced geological interpretation resulted in the conversion of 29 million tonnes @ at 1.1 grams/tonne gold and 12 grams/tonne silver from inferred to indicated categories. This is an increase of 230% to indicated tonnes. The decrease in silver content in the resource is due to 1.4 million ounces of mining depletion and a slightly more conservative estimate of the geological controls to silver mineralisation. Inclusive of mining depletion, 350,000 ounces of gold were added to and 300,000 ounces of silver were removed from the estimated mineral resources.
The ore reserves occur within three open pits (Purnama, Barani and Ramba Joring) which contain an associated 68.9 million tonnes of waste material to be mined, resulting in a total waste material to ore reserve ratio (strip ratio) of 1.4-to-1.