The Bootu Creek manganese deposits are strata-bound, located at the contact between the underlying dolomite-siltstone Attack Creek Formation and the overlying ridge forming sandstone of the Bootu Formations in the Tomkinson Group, within the Ashburton Province of the Palaeozoic Tennant Creek Inlier.

The mineralised horizon is folded around the gentle NNW plunging Bootu Syncline, can be traced 24km and dips around 30o towards the fold axis.

The manganese mineralisation is located in shallow marine sediments, which can locally retain a relic stromatolite texture, and is supergene enriched within a deeply weathered profile.

Ore widths vary from 3m to 15m and ore mineralogy consists predominantly of Pyrolusite and Cryptomelane in a silica rich gangue within the supergene zone, above a Rhodochrosite and Braunite unweathered zone at depths of greater than 90 m from surface.

All current and planned mining is by open pit mining methods. Open pit slope angles, determined by an Independent Geotechnical Consultant, are at an overall angle, including berms, of 45o to 55o for hanging wall and end walls, and with footwall batter angles not exceeding the local bedding planes.

Mining at the Bootu Creek Mine is carried out using a conventional open-cut method of mining, blasting and excavation using hydraulic excavators and dump trucks.

The mining strategy was centred around two fleets focussed on the east limb deposits of Gogo, Shekuma and Chugga Far North.

Mining is now completed in the Gogo, Chugga South and Chugga North pits on the east limb and mining commenced on the Tourag pit on the west limb late in 2018.

For 2019/2020, mining is/will continue on the east limb in Chugga Far North and with a planned cutback in Shekuma. With mining on the west limb continuing in Tourag, commencing in Yaka and planned cutbacks in Masai, the mining operational requirement will increase to three digger fleets and 10 haul trucks. This will ensure a sustainable ore supply to the ROM as well as the building up of significant ROM stocks, de-risking the wet season weather impacts on the Bootu Mine operation.

Higher grade ores from the Shekuma and Yaka deposits and moderate grades from Tourag, Masai and Chugga Far North deposits, will form the basis of plant feed for the next 2 years maintaining the current processing plant mass yields.

The Bootu Creek plant is a relatively simple crushing and screening operation, followed by heavy media separation (HMS) to concentrate the manganese minerals. The plant is comprised of two separately built processing plants. The original primary processing plant (PPP) was commissioned in 2006 and processes the Run of Mine (ROM) ore while the secondary processing plant (SPP) commissioned in December 2009 abuts the PPP and selectively processes drum plant rejects and washed fines from the PPP and previously stockpiled drum plant rejects.

The PPP was designed to produce a nominal 550,000 tonnes of product per annum, comprising about 420,000 tonnes of lump and about 130,000 tonnes of fines. Numerous capital upgrading and improvements increased its production capacity to approximately 800,000 tonnes of product per annum. With the commissioning of the SPP in 2009, the combined production capacity from the two plants can approximate 1 million tonnes per annum dependent upon the characteristics of the ore being fed.