Forrestania’s camp of nickel sulphide deposits is hosted by a sequence of ~2.9Ga meta-igneous and metasedimentary rocks that are part of the Forrestania Greenstone Belt (FGB) of the Youanmi Terrane of the Eastern Yilgarn Craton.

Forrestania’s nickel deposits is the ‘Kambalda-style’ Type 1 and Type 2 models where nickel sulphides are interpreted to have accumulated in channelised komatiitic lava flows. Many of Forrestania’s deposits are often tectonically displaced from the original depositional locations and have been deformed and/or dismembered by one or more local and/or regional post-depositional tectonic events.

The main deposit type is the komatiite hosted, disseminated to massive nickel sulphide deposits, which include the Flying Fox and Spotted Quoll deposits. The mineralisation occurs in association with the basal section of high MgO cumulate ultramafic rocks.

The greenstone succession in the district also hosts several orogenic lode gold deposits, of which the Bounty Gold Mine is the largest example.

Spotted Quoll’s mineralisation is of a brecciated style, containing clasts of quartz and garnet schists, and occurs in and along a complex shear zone, which is overlain by BIF and metasediments. As is common in most ultramafic rocks in the Forrestania region, amphibolite grade metamorphism has destroyed any primary volcanic textures. The deformed mineralisation has also undergone hydrothermal alteration that has changed the sulphide minerology and locally introduced low concentrations of arsenic forms of sulphides.

Spotted Quoll is an underground mine which is a part of Forestania operation.

As end of FY22 mineral resources estimate extends to ~1.3km below surface, and ore mining has reached to a depth of ~1.0km.

The mining method at Spotted Quoll is long hole stoping with filling of the mined voids with paste. The minimum mining width is 3m and the length of stopes ranges from 10 to 30m, depending on geotechnical conditions and local mineralised lense geometry. Stope heights range from 7 to 15m.

The CBC treats the raw nickel and produces a consistent nickel concentrate product grading approximately 14% nickel. The concentrate produced from the Forrestania project is characterised by low impurities such as magnesium which makes it more desirable to smelters.

The concentrator consists of a three-stage crushing circuit, followed by a single closed-circuit ball mill and a system of flotation tanks and thickening/filtration system.

The recovery rates for Cosmic Boy currently average between 85% and 90%. The recovery rates refer to the percentage amount of nickel recovered from the raw ore during processing.

At CBC a Mill Recovery Enhancement Project (MREP) has recently been commissioned. The MREP incorporates the use of the Company’s BioHeap™ technology to recover nickel from the tailings waste stream. The nickel recovered is then converted into a high-grade nickel sulphide product which can either be mixed with the CBC floatation concentrate or s ........