THE Simberi Gold Project of St Barbara produced a record 30,430 ounces during the March quarter at an all-in-sustaining cost (AISC) of A$1025 per ounce. This exceeded the 28,057 ounces produced in the previous quarter at an AISC of A$1277 per ounce.
St Barbara said the improved AISC was due to higher production and improved grade and recovery, together with the benefit of lower ore handling costs. Grade improved to 1.14 g/t from 1.13 g/t in the December quarter.
Total material moved in March quarter was 3.5 million tonnes, down on the previous quarter due to planned maintenance of the excavator fleet and lower strip ratio. The strip ratio decreased to 2.4, consistent with the life of mine plan. The company said the high intensity program of pre-stripping required to access new ore sources at Sorowar and Pigiput was largely complete.
Plant recovery improved to 85% from 83% due to ongoing improvement in ore and waste mining identification and selection, improved quality ore, particularly from Pigiput, as well as incremental operational improvements in the processing plant.
The company has increased its 2017 guidance for Simberi from 95,000-105,000 ounces to between 105,000 and 110,000 ounces at an AISC of between A$1285 and A$1330 per ounce, down from between A$1330 and A$1490. Proposed capex is unchanged at between A$4 million and A$5 million.
At Tatau Island trenching, mapping and drilling continued at the Southwest Tatau project during the March quarter targeting high-grade sulphide-oxide gold mineralisation at Mt Tiro, Mt Siro and Seraror prospects.
A detailed topographic map was generated from airborne LiDAR (light detection and ranging) survey flown in the December 2016 quarter to support regional exploration.
A 43 line kilometre ground magnetic survey was completed in March. Areas covered included access tracks around Southwest Tatau as well as a soil grid over Talik.
Diamond drilling at Southwest Tatau continued during the March quarter with nine diamond holes for 748.1 metres completed. Eight trenches were completed at Mt Siro with results including 25 metres @ 1.7 g/t, 75 metres @ 2.3 g/t, 10 metres @ 3.1 g/t and 30 metres @ 1.2 g/t.