The Savannah sulphide rich nickel, copper and cobalt orebody is hosted by the layered mafic-ultramafic Savannah Intrusion which is enveloped by aluminous metasediments and para-gneisses of the Tickalara Metamorphics. The Savannah Orebody is mostly confined to a marginal norite unit up to 40 metres thick developed above the base of the intrusion. Areas of massive, matrix and disseminated sulphide mineralisation, dominated by pyrrhotite, chalcopyrite, pentlandite and minor pyrite occur throughout the marginal norite unit.

The majority of the ore was mined via long-hole open stoping, which is a highly mechanised and low cost method. Access to the top and bottom of the ore block is established with tunnels, a slot raise is created, and holes are then drilled to blast vertical slabs off the ore block. Once the ore block has been blasted and extracted, the stopes are filled with paste (tailings and cement mix) to stabilise the void and allow extraction of adjoining ore blocks. The minimal waste material mined is either stockpiled underground or trucked to surface.

The process plant at Savannah comprises a single stage crusher, SAG mill, flotation, thickening and filtering stages to produce a bulk nickel, copper, cobalt concentrate. Metallurgical recoveries average 86-89% for nickel, 94-97% for copper and 89-92% for cobalt. The plant was originally designed for a throughput of 750,000 tonnes per annum, but has consistently outperformed the design specifications. Recent plant trials indicate the plant can operate at in excess of 1 million tonnes per annum.