Pedra Branca East (PBE) is an Iron Oxide Copper Gold (IOCG) type deposit located within the Carajás Basement, and is hosted predominantly by diorite and sheared granite. Country rocks are mostly biotitegneisses (ortho-gneisses), while pegmatite dykes are abundant in proximity to the ore zones.

This deposit occurs along an E-W striking regional shear zone, which is represented by metres wide mylonitic zones marked by intense silicification. This shear zone is regionally crosscut by north-south, northeast and northwest striking faults.

PBE consists of a single continuous orebody, which strikes east-west and has a >600m strike extension. It is a sub-vertical to steeply dipping (south) plunging shoot, with a thicker higher grade central core which follows the plunge. The orebody begins to shallow out in dip at depth, >400m below surface and beyond.

The ore zone itself is typified by zones of high grade breccia matrix ore (fragments of hydrothermal breccia cemented together by semi massive sulphides), which are interspersed with zones of lower grade disseminated mineralisation. The most dominant of the high grade zones is the Hanging Wall High Grade Zone (HW-HGZ), which sits on the hanging wall contact and is present across the entire depth and breadth of the PBE orebody. The hanging wall high grade zone has a sharp and easily identifiable “knife edge” contact.

Two main ore types are identified:

• Semi-massive, high grade breccia matrix ore: consists of hydrothermal breccia zones with matrix filled by magnetite and chalcopyrite, plus subordinate pyrrhotite and less pyrite. The clasts are made of altered host rock and coarse amphibole. The typical range of assays for this ore type is between 4.0% copper to 10.0% copper.

• Disseminated ore: a low to medium grade ore which envelops the high-grade zone. It consists of the same sulphide assemblage, which is also associated with magnetite that occurs as fine disseminations in the host rock, sometimes following the foliation, and also filling veinlets and fractures. The typical assays range from below cut-off grade (0.9% copper) to 2.5% copper.

The box cut, portal and initial few metres of decline was completed in 2016 and much of the infrastructure to resume its initial excavation is in place.

Sublevel stoping was selected as the mining method and has been deemed suitable for the orebody, based on orebody geometry and rock mass qualities.

Detailed infrastructure design was completed upon the mine design to address the required mine ventilation, mine dewatering, power supply, controls, and communication requirements.

The mine plan targets a ~1 Mtpa10 production rate, achieved in Q1 2022 with a total mine life of 8 years. Sublevel stoping with rock backfill will be applied in a bottom up bench stoping configuration. Stopes will be mined via long hole open stoping.

The pre-concentration and development waste will be utilised as backfill.

An ore sorting plant will be built at Pedra Branca. Test work for pre-concentrate utilised Pedra Branca core sample composites analysed through a sorting machine containing different sensors. A larger 6 tonne lower grade Antas North sample was also tested at an industrial scale. The test work indicated similarities between the ores. Based on these test results, an anticipated ~55% reduction in volume for ~93% recovery of copper metal is estimated.

The pre-concentrate process raises the average ROM ore grade from ~2.0% Cu, ~0.5g/t Au to ~4.4% Cu, ~1.2 g/t Au with an associated ~55% reduction in tonnage, significantly reducing transport costs to the Antas processing facility. This also reduces the environmental and social impacts associated with trucking and tailings facilities.