The southern cutback to the existing Belinau open pit at Sumatra Copper & Gold’s Tembang project has advanced as planned with the first underground development drive now into high grade gold and silver-bearing ore on Level 1.
The re-optimized mine plan provides a second access into the Belinau ore body from underground to deliver additional high grade feed to the processing plant which is now operating at nameplate capacity.
Gold and silver assay results received up to November 20 from grade control face channel samples along this ore drive have been impressive. The results exceed resource model estimates and confirm the high grade nature of the deposit even at the outer margins of the resource.
A sample at Cut 11 returned 1.5 metres @ 30 grams/tonne gold and 1053 grams/tonne silver, and a sample at Cut 10 returned 2 metres @ 20 grams/tonne gold and 280 grams/tonne silver.
Exposures of the vein from the underground portal area exhibit epithermal textures and banding commonly associated with the high grade mineralization at Belinau.
Open pit development is progressing as planned with Berenai and Asmar supplying the majority of ore to the processing plant.
The combined effect of commissioning the processing plant eight weeks ahead of schedule, the earlier than anticipated ramp-up of the plant to nameplate capacity and a delay in the permitting and delivery of explosives has led to a shortfall in supply of high grade ore from the open pits and the Belinau underground mine.
The company is therefore focusing on establishing multiple underground development headings at Belinau to accelerate high grade ore production. Fine tuning of the open pit schedules is also continuing with a view to optimizing the delivery of higher grade ore.
The gold and silver head grade at the processing plant has progressively been increasing as planned and is expected to steadily increase as higher grade ore is accessed from the open pits and underground.