Poised to become a mid-tier gold producer

The Witwatersrand Basin deposits, such as that found on the Burnstone Property, generally represent gold concentrations, called placer deposits (or “reefs”, in local mining terminology), hosted within coarse-grained sediments (conglomerates) deposited in braided stream channels on broad river plains. Economic gold concentrations commonly extend for several km down the dip, and for up to 50 km (30 mi) along strike of the sedimentary rock units. Gold occurs as detrital grains in nugget-like shapes and secondary (re-crystallized) grains, ranging in size between 0.005 and 0.5 mm diameter.

The Witwatersrand Basin has been affected by several structural events. Many studies now differentiate between deformation that was taking place during deposition of the Witwatersrand sediments and subsequent deformation. Deformation that occurred during the deposition of the sediments played a key role in the distribution and thickness of the host rocks as well as the occurrence of the gold-bearing reefs. Later faulting and buckling of the sequence determined which parts of the basin remained buried, and the depths to mineable horizons.

The South Rand area is located in the north eastern part of the Witwatersrand Basin. In the South Rand, the Witwatersrand sequence is thinner than in other parts of the Basin. The West Rand Group, comprising about 1,500 m (4,920 ft) of alternating quartz arenite and shale units, unconformably overlies the Archaean granite-greenstone basement rocks. The overlying Central Rand Group strata are approximately 900 m (2,950 ft) thick and include the Kimberley Reef horizon, which is the main gold-bearing unit on the Burnstone Property. The Johannesburg Subgroup, including the Bird amygdaloidal lava and the Kimberley shale, is about 300 m (985 ft) thick. The Turffontein Subgroup is approximately 600 m (1,970 ft) thick and is made up of a sequence of quartz arenites and conglomerates that correlate with the Elsburg Formation.

An 18-km (11-mi) long northwest-southeast gold trend has been outlined on the Burnstone Property that appears to be associated with a large, ancient, braided channel system extending over the property. Drilling has also shown that two northwest-southeast trending sub-parallel faults, spaced four km apart, have uplifted the central portion of the gold corridor. As a result, a substantial portion of the gold-bearing horizon along the main deposit trend lies between 250 and 750 m (820-2,640 ft) in depth, which is relatively shallow for Witwatersrand gold deposits. The average thickness of the reef is 35 cm.