Societe d’exploration Miniere du Haut Katanga (Semhkat)
Mwana interest:
Mwana has a 100% beneficial holding in the prospect (a part of which is subject to a Joint Venture and Option Agreement with Anglo American).
Geology and history:
Kibolwe: The Kibolwe prospect, 160 kilometres north-west of Lubumbashi, is a significant secondary enriched sediment-hosted stratiform copper deposit hosted by Mines sub-group rocks. The dominant copper oxide mineral is malachite with minor amounts of cuprite and tenorite, which occur within weathered argillaceous carbonate and shale units. Copper sulphides of chalcopyrite and chalcocite occur at depth. RC and core drilling programmes have outlined a near-surface, flat-lying mineralised zone up to 40 metres thick extending over a strike of 1,200 metres. An indicated mineral resource, suitable for open-pit mining, has been modelled for the drilled portion of the mineralisation. A conceptual mining study on this resource has indicated it to be sub-economic at the current size. Several similar anomalies, which have the potential to add to the total resources of the area, have been identified in the vicinity of Kibolwe. A larger structure to the west, with similar geology to Kibolwe, had one core hole drilled in it, which intersected shallow mineralization of the Kibolwe type. The area is expected to produce substantial additional copper resources.
Kiamato: A sediment-hosted stratiform copper-cobalt occurrence has been identified at Kiamato, 4 kilometres northwest of Kibolwe. Mineralisation occurs within a 700-metre strike length of Mines Sub-group strata. A preliminary 500m core drilling programme was completed at the end of 2008 to delineate the strike and down-dip potential of the copper-cobalt mineralisation. Encouraging mineralized intersections were made in a number of the holes.
Mwombe: Exploration on the Mwombe prospect has identified mineralised Mines sub-group strata outcropping over a 600-metre strike length. Assay results from trench and pit sampling programmes have yielded elevated nickel and cobalt concentrations (up to 2% Ni and 0.38% Co over 1 metre) as well as gold, platinum and palladium (up to 1.1g/t Au, 0.1g/t Pt and 0.1g/t Pd). A 1,700 metre core drilling programme was completed in the third quarter of 2008 having intersected several encouraging mineralized units.
Mukema: The early-stage Mukema prospect has breccia-hosted copper-silver mineralisation developed within Kundelungu sediments. The breccia contains malachite, chalcopyrite and chalcocite along a 700-metre strike length. In places the mineralised breccia is 40 metres wide and coincides with a 4-kilometre long thrust fault zone highlighted from the aeromagnetic and radiometric data. Pit sampling of the breccia has yielded copper and silver values of up to 37% copper, 60g/t gold and up to 439 g/t silver over 1 metre.
Maniamuna Concessions (Kasai): Regional geochemical soil sampling programmes have been designed to follow up observed anomalies at Kafakumba, a sediment hosted copper target, and Lulua, a magmatic nickel copper-sulphide target in the south of the Maniamuna concession area.
Anglo American Joint Venture: The airborne electromagnetic (SPECTREM) survey, completed in 2008 over the North West Block and Lombe, identified several significant exploration targets. Mapping and geochemical soil sampling programmes were completed over five targets some of which reported elevated copper and nickel values (up to 428 ppm Cu and 870 ppm Ni). Rotary Air Blast and air core drilling programmes have been planned to test some of these targets.
Ambase has undertaken further exploration over the Lombe permit identifying additional zinc and copper soil anomalies and mineralised strata. A 1,200m core drilling programme is planned to test two target areas within the permit area.
Current status and prospects:
As a result of the decline in the outlook for commodity prices, especially in the second half of the year, base metals exploration activities were scaled back significantly, while ensuring that conditions to retain exploration rights are satisfied. Nonetheless, Core and Reverse Circulation drilling programmes were completed on the Kibolwe, Kiamato and Mwombe prospects, and limited reconnaissance exploration on the Mukema, Kamungoti, Kintungulu copper prospects continues to locate significant copper and gold anomalies.
Nyundeulu: Small flattened nodules rich in black cobalt oxides
Kiamato: Blocks of RSC taken from trench, coloured in pink by cobalt salts
