Sumatra Copper & Gold updates Tembang gold operation
Friday, February 19 2016 - 10:05 AM WIB
ASX-listed Sumatra Copper & Gold plc has been progressively ramping up operations after pouring its first gold on Sept. 2015, the firm said in its latest operation update.
During January 2016, the company processed 39,065 tons of ore at a grade of 2.65 g/t AuEq1 (1.81 g/t Au and 62.5 g/t Ag) at a recovery of 88.9% Au and 69.3% Ag to produce 2,750 gold equivalent1 ounces (2,025 oz of gold and 54,374 oz of silver).
The plant operated at an annualized rate of 460,000 tons during January, 15% above nameplate capacity.
Further metal production increases are expected over the coming months as ramp-up of mining operations progresses and mine grade increases with depth.
Belinau underground mine development
In January 2016 a milestone was achieved with the successful completion of the first stope on Level 1. Ore development is continuing on Level 2 with benching currently in progress. Upon completion of benching, the ore exposed in the ore drive floor will be trenched (to a width of 1.2m). This is expected to produce high grade ore with minimal dilution. Following the completion of trenching the narrow excavation will be filled with cemented rock fill to allow waste to be backfilled; this will facilitate the commencement of drilling and stoping of the high grade stope block between Level 1 and level 2. This development strategy has been successful in achieving 100% ore recovery without any requirement for residual ore pillars for geotechnical support.
A further milestone has been achieved with the main decline becoming fully operational. As previously announced, the main decline had encountered difficult ground conditions which resulted in the decision to incline towards the main decline from Level 2. Ventilation will now be greatly improved along with the ability for the underground mine trucks to enter the mine and significantly improve haulage productivity. Ground conditions have improved markedly and the main decline is on track to access Level 3 during the current quarter. Level 3 will be the first level to access the full strike length of the Belinau main vein providing development ore with drives of up to 250 meters in length. Level 3 will also provide access to the Bitu north vein and potentially the Bitu south vein.
Discovery of new vein at Belinau
During mining of the Belinau east cutback in January 2016 a new vein was discovered in the south wall of the Belinau pit. This vein is believed to be the southern extension of the Bitu vein that has previously been drilled on the northern side of the pit (refer to September 2013 Quarterly Report). Surface sampling of the exposed vein returned grades of up to 8.87 g/t gold. Historically drilling would have been parallel to this structure. Diamond drillhole BTD1221 intersected 2m @ 18.9 g/t Au and 175.5 g/t Ag from 23m downhole depth and potentially intersected a parallel vein to the Bitu South vein but has yet to be adequately followed up.
To follow-up this intersection, and to determine the orientation, width, strike and depth extent of the new Bitu South vein structure, resource drilling is planned to commence in March 2016. Any additional ounces added to the existing Ore Reserve may provide a significant potential uplift in profitability of the Belinau underground operation.
Editing by Johannes Simbolon