A major polymetallic discovery in recent drilling by Robust Resources has greatly expanded the potential of the Batu Perak system within Lakuwahi Caldera prospect on Romang Island. One recent hole intersected strongly mineralized polymetallic breccia 160 metres thick.
The hole was drilled as part of a series of holes designed to explore the extensive stratabound Volcanogenic Massive Sulphide Target (VMS) at Batu Perak. The hole has an upper silver-rich cap with gold and base metal rich zones deeper down. Grades averaged 1.22 grams/tonne gold equivalent and 2.3% base metals.
The polymetallic breccia lies 250 metres southeast of the VMS system and the expected geological relationship between the two will be determined through follow-up drilling.
The hole represents another highly significant intersection on Romang Island and features mineralization that started at a shallow depth of 6.3 metres and ended in mineralization at a final depth of 166.7 metres. The breccia zone is open substantially in all lateral directions and at depth.
Results include 160.4 metres @ 1.22 grams/tonne gold equivalent and 2.3% combined base metals from 6.3 metres (0.61 grams/tonne gold, 32 grams/tonne silver, 0.10% copper, 1.25% lead and 0.96% zinc), including 13 metres from 22 metres @ 5.02 grams/tonne gold equivalent and 1.42% combined base metals (0.69 grams/tonne gold, 229 grams/tonne silver, 0.03% copper, 1.36% lead and 0.03% zinc); and 22 metres from 65 metres @ 1.89 grams/tonne gold equivalent and 4.04% combined base metals (1.10 grams/tonne gold, 42 grams/tonne silver, 0.21% copper, 2.43% lead and 1.39% zinc).
Robust’s managing director Gary Lewis says the hole is “one of the most significant intersections encountered to date within the Lakuwahi Caldera prospect. The current interpretation is that it is part of the feeder system for the exhalative VMS-style mineralization currently being explored at Batu Perak. The continuous grades over a very long interval means this breccia is a new target in itself with significant discovery potential.
“Results follow on from a particularly encouraging program of exploration drilling, transforming the world-class potential of the project on Romang Island. The processing focus has now moved towards researching the optimum flowsheet to treat the large polymetallic deposits currently being delineated.
“Robust continues a very active program on Romang Island with eight owner-operated rigs turning across Balu Perak VMS and breccia targets, the Batu Mas Deeps has high-grade massive sulphides, the exciting silver discovery of Batu Putih, and the Batu Hitam Basin flats,” Gary Lewis adds.