The proximal nature of a variety of mineralization styles within the SBS28 Complex is indicative of a single large mineralized system. The controls on mineralization are becoming better understood as drilling progresses.
The majority of drilling in 2012 focused on infill and resource-extension work required prior to the final open pit optimization and mining studies. The 2012 drilling program successfully defined extensions to mineralization which form the basis of South Kalgoorlie's open-pit production from Q2 2013.
Drilling completed in 2012 also confirmed the continuity of higher grade mineralization immediately below the historical underground workings at both the Barbara and Surprise Mines with results including 3m at 8.2g/t gold from 299m in drill hole BU212 at Barbara, and 2m at 12.7g/t gold from 196m in drill hole SD075 at Surprise. Alacer has recently completed two wide-spaced step-out drill holes to assess the depth potential of these two historic high-grade mines. Drill hole BU210W1 at Barbara intersected 4.25m at 7.7g/t gold from 558m and drill hole SD083 at Surprise intersected 2.1m at 9.1g/t gold from 386.5m (estimated true width is 60-70% of downhole width). Both drill hole intersections occur over 200m below the existing underground workings and confirm the significant underground potential of both these mines.
The 2013 exploration focus is to test the underground potential of the historic high-grade SBS28 mines, as well as test for new discoveries where minimum effective shallow exploration has been completed.
Mt. Marion Complex
The Mt. Marion area is the third SKO target area to be drilled during 2013. The Mt. Marion deposit contained in excess of 1 million ounces of gold and was mined by open pit and underground methods in the late 1990s to mid 2000.
No regional drilling has occurred outside the immediate mine area since the 1997 discovery of Mt. Marion. Alacer plans to test an area around the Mt Marion deposit which lies on a +5km long and +1km wide dilational bend of the mineralized Karramindie Shear. Only 1km of this mineralised structure has been tested in the immediate vicinity of the Mt. Marion deposit. Early-stage reconnaissance drilling in the remaining 4km of this prospective area is planned to commence in April.