WA Southern Cross

Gold areas represent exploration licences.

Exploration at Southern Cross has several aspects, covering extensions to the existing mine at Marvel Loch and re-evaluation of over 20 targets, many of them old open pits, within a short distance to the Marvel Loch plant.

Marvel Loch Underground

Exploration has defined underground resources of 7.3 million tonnes @ 3.6 g/t for 832,000 ounces at Marvel Loch. The deposit comprises a number of steeply-plunging cylindrical-shaped quartz-veined lodes, with ore thicknesses from 4 to 30 metres wide. Vertical continuity of deposits is strong. There is considerable potential for increasing resources further at depth. Exploration drill drives have been developed in the north and central parts of the mine to allowing further resource extension drilling in the year ahead.

Southern Cross New Mine Exploration

Site-based exploration teams were formed during the year to explore systematically for new mining opportunities in proximity to the Marvel Loch plant. This has involved the compilation, validation, ranking and testing of various targets, with an emphasis on accurate interpretation of orebody controls. Proven and Probable Ore Reserves at Southern Cross have increased from 600,000 ounces to 911,000 ounces as a result of successful drilling at Nevoria and Transvaal. 

Exploration is currently focussed on definition of high-grade resources at Jaccoletti and GVG Lode 1. Recent drilling from Jaccoletti has significantly upgraded the potential for underground development, with results including 54m @ 8.1 g/t from 243m, 21m @ 12.2 g/t from 317m and 18m @ 7.6 g/t from 244m. These intersections form the core of a steep southeast plunging ore shoot with true widths in excess of 20m and a potential high grade strike length of 50-80m.

Base Metals

At Southern Cross, drill core is being relogged and sampled to prioritise the ultramafic units on which to focus further nickel sulphide exploration. Preliminary results show some similarities to the Western Belt at Forrestania, which hosts the Flying Fox deposit. This evaluation is being supported by a cutting edge scientific research initiative which St Barbara has sponsored through the CSIRO and the University of Western Australia.

The copper-zinc potential of the Southern Cross district is also being evaluated. Some regions show anomalous base metal concentrations, with up to 14.3% zinc, 115 g/t silver, 4.6% copper 2.1% lead from historical drill core from one prospect area. Previous studies suggest these metals may have been hydrothermally remobilised from a volcanic hosted metal sulphide deposit. Follow-up geophysical surveys have identified further electro-magnetic conductors which may represent strike-extensions to the mineralised stratigraphy.

Map of Operations

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