The original 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.

Prior to the development of the Savannah Open Pit, the marginal norite unit outcropped as a prominent 250 metre long limonite-goethite gossan with fresh sulphide mineralisation developing approximately 20 metres below surface. At approximately 500 metres below the surface, a significant sub-horizontal fault, the 500 Fault, cuts the orebody and offsets it 200 metres to the northwest. A similar fault at approximately 900 metres below surface, the 900 Fault, offsets the orebody a further 250 metres to the northwest. Mineralisation above the 500 Fault is referred to as the “Upper Zone”, between the 500 and 900 faults as the “Lower Zone” and below the 900 Fault as the “sub 900 Fault Zone”.

Ore production is undertaken via conventional long hole open stoping with remote bogging on retreat. Currently, the long hole drilling is undertaken by a contractor. Savannah purchased a used Cabletec drilling rig for ground support and as a backup production drill, as required. The mine plan requires open stopes to be backfilled with cemented paste fill to maximise recovery of the orebody and to assist geotechnical stability of the mine.

Savannah ore has been successfully treated through SAG mill since commissioning in 2004.

Subsequent to the restart further works were completed including the replacement of the Jaw crusher and SAG mill motor. A full set of filters plates is onsite ready for installation.

The Savannah processing plant consists of conventional crushing, grinding, flotation, and concentrate handling, producing a bulk nickel-copper-cobalt concentrate for sale to third-party. The nominal throughput capacity of the Savannah plant is approximately 1.0Mtpa.

The Savannah plant operated continuously from August 2004 to May 2016, with continuous improvements in recoveries and throughput achieved from changes in operating practices and minor circuit modifications.

Prior to restarting in in December 2018, the processing plant was refurbished at a cost of $12M, with work encompassing refurbishment of the ROM bin, apron feeders, conveyors; a SAG mill reline; all pumps; flotation cells including replacement of cleaner cells; refurbishment of thickeners and the concentrate filter; enclosing the courier on stream analyser and replacing key components; installing fusion furnaces and installing an XRF in the laboratory. At the paste plant the paste disc filters were ........