La Demajagua has the characteristics of a low sulphidation epithermal gold deposit. The geology of the deposit area is dominated by schistose units (quartz-graphite schists, quartz-sericite schists, and quartzites, rich in gold-bearing arsenopyrite, typically metamorphosed to greenschist facies.

The lithologies alternate between packages of graphite rich and relatively graphite poor, with package thickness of 20-200m, though increased graphite content occurs in almost all cases of fault brecciation, and so in turn mineralisation is almost always found with areas of elevated graphite content.

Alteration indicates low temperature formation and occurs as rare bleaching of rocks (only occurring in the vicinity of quartz veins over tens of cm in thickness), pervasive sericitisation,
graphitisation, and silicification either as a saturation of the entire rock mass with silica or by the formation of a network of quartz veinlets.

Vein quartz is grey, white-grey or clear and is finely crystalline. Evidence of several episodes of remobilisation can be found in the quartz, and finely disseminated sulphides occur in all areas of silicification and partly outside. Hydrothermal flow is assumed to have been aided by hydraulic pumping from fault movement, with the average sulphide content in the order of 4-6% and increasing up to 15% in enriched areas.

The gold is primarily held within arsenopyrite and associated with boulangerite. Ore text ........

The proposed open pit mining is expected to be a straightforward operation with mining to a depth of approximately 150m, and though the stripping ratio is relatively high the project will benefit from reasonably soft waste material.

Overall Pit Slope Angle - 38 Deg.
Minimum block size in Model - 5x5x5 m.

The mining fleet will be supplied by Chinese manufacturers of high quality equipment, as will the concentrator.

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