The Kalpini Project is located 75km northeast of Kalgoorlie, approximately halfway between the Lindsay’s and Kurnalpi fields.
The Kalpini Project comprises the Gambia and the Atlas trends, with Gambia being the larger and higher grade of the two. Exploration work has found that these two lines of quartz veined mineralisation have contrasting geology and structural control, with flat and steep mineralised orientations (Gambia and Atlas respectively). Geological mapping during 2012 has identified additional mineralised quartz veins along strike of Gambia and Atlas and of contrasting structural orientation.
Gambia is a strong gold mineralised north-west trending structure with a gold mineralised corridor extending over a kilometre in length. The narrow mineralised alteration envelopes within the dolerite host rock have a near flat-lying orientation.
Exploration activity to date has been mainly focused on Gambia, with an initial pit design and Initial Probable Reserve for the prospect completed towards the end of 2012. It is estimated that an initial open pit mine could deliver 567,000t of ore at a grade of 2.75 g/t for 50,040oz of gold, over two years. The initial pit design is based on an optimised $1,500/oz shell, mining to a depth of 55m and considers the delivery of both oxidised and fresh ore to the Carosue Dam mill. Metallurgical test work has also demonstrated the ore to be free milling, with good recoveries.
Planning has indicated that the Kalpini project could be brought into production as an open pit mine and in preparation for this environmental and heritage surveys have been completed and a miscellaneous licence for a planned haul road linking Kalpini to the Carosue Dam haul road has been approved. Scope also exists for a future underground mining operation, but that option is yet to be thoroughly investigated.
Reverse circulation (RC) drilling of the Atlas prospect was undertaken in 2011 and encouraging results, in terms of grades and continuity, were received. Gambia remains to be the focus at Kalpini, so further exploration work has been limited. Historical work however, reported the Atlas shaft to have produced 7,806oz of gold from 15,218t of ore, at an average grade of 16.5g/t.