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.

The process plant at Savannah was commissioned in August 2004 and comprises a single stage crusher, SAG mill, flotation, thickening and filtering stages to produce a bulk nickel, copper, cobalt concentrate. Over the 2004 to 2016 initial operating period, metallurgical recoveries averaged 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 consistently outperformed the design specifications with rates exceeding 1 million tonnes on an annualised basis.

The Processing and Paste Plants were refurbished by MACA Interquip between June 2018 and February 2019 and the Processing Plant was recommissioned in December 2018. The major refurbishment works undertaken included:
- Repair and/or replacement of corroded structural steel and painting throughout;
- ROM orebin refurbishment and replacement of the grizzly;
- Refurbishment of the crusher:
- Refurbishment of the emergency stockpile bin and conveyors;
- Installation or repairs to rubber lining in flotation cells;
- Installation of new lifters and liners in the mill and replacement of trunnion bearings;
- Refurbishment or replacement of most pumps;
- Thickener tanks refurbished;
- Electrical and communication upgrade including replacement of existing PLCs;
- Major refurbishment of the filter press;
- New on-stream analyser.