The key setting for all the nickel that has been mined historically at Kambalda district is at a contact zone between two rock types, with a younger overlaying volcanic rock.

The Mincor Nickel Operations (MNO) is expected to consist of Cassini and the Northern Operations (Long and Durkin North) at commencement, with the Miitel mine contributing in the back half of the project life.

Cassini
Cassini is located on the southern section of the Widgiemooltha Dome. The geology of the Widgiemooltha Dome and the area to the south consists of a thrust repeated sequence of basic ultramafic extrusive and intrusives, with intercalated sediments and acid volcanics with nickel sulphide orebodies found at the base of the ultramafic sequence.

The Cassini orebody as interpreted in the Mineral Resource is split into eight lodes, labelled CS2-CS9. From a mining perspective, the Mineral Resource has been delineated into two main areas based on spatial characteristics. These mining areas have been named by the dominant lode (CS2 or CS4). The CS2 Area (CS2, CS3, CS6, CS7 and portion of CS5 lodes) consists of east-west trending parallel lodes, mainly offset, dipping at ~45° to the south with thickness from ~1m to ~7m, averaging 3m.

The CS2 Area extends from ~260mRL (approx. 50mbs) to ~-240mRL (480m vertical extent). Grades and orebody thickness are inconsistent above ~75mRL.

The CS4 Area (CS4, CS8, CS9 and portion of CS5 Lodes) consists o ........

The Definitive Feasibility Study has adopted an underground contractor model for mining costs.

The primary mining method proposed is bottom-up longitudinal longhole stoping (LHS) with modified Avoca assuming cemented rockfill (CRF).

Cassini
The Cassini mine will be accessed via a new box-cut and portal. Capital works for the box-cut, commenced in February 2020 and are expected to be completed by April 2020. The stope optimisation process showed that the economic portion of the Cassini orebody (commences from 250m below surface). Based on geotechnical analysis and the results of geotechnical drilling, the box-cut has been located ~700m to the south of the orebody where near-surface ground conditions are more favourable.

A twin decline system will be developed from the box-cut zone to the production zone, with access and return air declines excavated in parallel, allowing primary ventilation to be established early in the mine life. Ventilation and secondary egress will be via a raise system developed from the ventilation decline to the box-cut.

Vertical sub-level intervals are 15m floor-to-floor, allowing good drill and blast control. Areas with no top access (i.e. crown stopes or levels directly beneath sill pillars) will be mined using conventional longhole open stoping, retaining in-situ pillars for support. Maximum open stope strike lengths of 30m have been applied based on geotechnical studies. Slots to open stoping spans ........

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