The KOTH mineralisation is considered to be part of an Archean Orogenic gold deposit with many similar characteristics to other gold deposits within the Eastern Goldfields of the Yilgarn Craton.

Gold mineralisation is associated with sheeted and stockwork quartz vein sets within a hosting granodiorite stock and pervasively carbonate altered ultramafic rocks. Mineralisation is thought to have occurred within a brittle/ductile shear zone with the main thrust shear zone forming the primary conduit for the mineralising fluids. Preexisting quartz veining and brittle fracturing of the granite created a network of second order conduits for mineralising fluids.

Brittle fracturing along the granodiorite contact generated radial tension veins, perpendicular to the orientation of the granodiorite, and zones of quartz stockwork. These stockwork zones are seen in both the granodiorite and ultramafic units and contain mineralisation outside the modelled continuous vein system (High Grade Veins).

Gold appears as free particles (coarse gold) or associated with traces of base metals sulphides (galena, chalcopyrite, pyrite) intergrown within quartz along late stage fractures.

The Western Flank mineralised zone strikes 30 degrees west of true north over a distance of 700m and plunges to the southwest. Individual lodes dip east at 35 to 45 degrees. Eastern Flank mineralisation strikes 30 degrees east of true north over a distance of 700m and is vertical. Stockwork mineralisation runs along the contact of the granodiorite/ultramafic contact which strikes 30 degrees east of true north over a distance of 4km and is vertical. Mineralisation has been tested to approximately 400m below surface and remains open.

The mining methods for underground is a mix of narrow to large scale open stoping and air leg room and pillar. Minimum height is approximately 3.8m with Jumbo development and 3.0m for air leg development with the resource reported on similar size panels to reflect this relationship.

KOTH is currently an operating underground gold mine, and the KOTH FFS is predicated on the continuation of existing underground mining practices. Mine design parameters are based on current site guidelines, which are well understood and have been successfully implemented.

The proposed primary mining method is long-hole open stoping, with minor amounts of airleg stoping in flat dipping areas of the orebody (<1% of ore tonnes). Stoping will follow a top-down sequence, commencing at the extremities of each level and retreating to the level access. Rib pillars will remain between adjacent stopes to maintain mine stability. The proposed mining methods and sequence are generally a continuation of current operating practices at an increased production rate.

Areas identified for long-hole stoping are categorised as narrow vein or bulk stoping. The narrow vein parameters include a 2.0 m minimum stoping width in combination with a 20 m level spacing, whereas the bulk stoping parameters include a 3.0 m minimum stoping width in combination with a 40 m level spacing.

Cut-off grades were estimated for the different mining methods, and stope shapes were generated using MSO software based on a provisional cut-off grade of 1.8 g/t.

A mine development design was created to match the stope optimisations. Modifying factors based on geotechnical evaluation and historical performance were applied to the mine plan and schedule. Mining dilution of 10% and mining recovery ranging between 85% - 95% was applied dependent upon the mining method.

Mine infrastructure requirements have been included in the mine plan, including power, water, emergency preparedness, and ventilation. The latter has been evaluated in simulation software and accounts for life of mine ventilation requirements.

The underground mine is planned to be accessed via the existing portal located in the KOTH open pit.

The assumed operating regime at KOTH involves the use of a mining contractor, consistent with current practices. The incumbent mining contractor (Pit N Portal-Emeco) has reviewed the mine plan and schedule and provided a detailed cost estimate for the FFS underground mining costs.

Underground mining may continue beyond FY27 as a result of further in-fill and exploration drilling. Extensional drilling will benefit from the installation of drill platforms as development progresses. The extension of the underground mine life would allow the mine to continue to produce at peak gold production rates and a lower AISC beyond FY27.

The KOTH underground ore, which is a continuation of the open cut mineralisation, is currently being treated at Red 5’s Darlot processing plant, which – like the proposed KOTH processing plant – comprises a conventional milling, gravity recovery and carbon-in-leach (CIL) circuit.

The KOTH processing facility has essentially been designed to process 4Mtpa of fresh open pit and underground ore. However, allowance has been incorporated into the design for future throughput upgrade to 6Mtpa with limited production interruption and low capital requirements. The primary crushing circuit has been designed for 6Mtpa. The mill selection and the layout of the grinding circuit allow for a future ball mill, with allowance provided for a second gravity recovery line. The design also allows for two additional future leach tanks and a tailings thickener (if required).

The processing plant will be designed to operate seven days per week at a nominal treatment rate of 500 dry t/h ........