The Antas North iron oxide copper gold deposit is hosted within the Carajás Mineral Province which is located in the southern part of the Amazon Craton. Locally the craton is overlain by metavolcanic–sedimentary units of the Rio Novo Group and the 2.76 Ga Itacaiúnas Supergroup. The Itacaiúnas Supergroup hosts all the known Carajás iron oxide copper gold deposits and is thought to have been deposited in a marine rift environment. The Carajás Mineral Province represents one of the best endowed mineral districts in the world and contains the world’s largest known concentration of iron oxide copper gold deposits including the, Salobo, Igarapé Bahia, Alemão, Cristalino, Gameleira, Furnas, Alvo 118, Antas, Pedra Branca and Pantera deposits.

The Antas North deposit is a structurally controlled iron oxide copper gold deposit which is spatially related to (WNW-ESE) regional shear zones, specifically the Carajás fault and the Cinzento shear system. Mineralisation is hosted within hydrothermal brecciated and altered felsic and mafic volcanic units. Mineralised fluids have been sourced from nearby large granitoid bodies and have been focussed along structural conduits resulting in the deposition of high grade (greater than 10 per cent copper) massive sulfide zones immediately adjacent to or within the interpreted main structural zone. These high-grade massive sulfide zones are commonly 2 to 5 metres wide and are surrounded by a broader zone of lower grade disseminated mineralisation grading 0.2 to 2.0 per cent copper.

The main zone of mineralisation at the Antas North mine has been defined over 350 metres along strike, 300 metres down dip and can be up to 35 metres wide. Mineralisation contains variable proportions of chalcopyrite, pyrrhotite, and magnetite. Mineralisation in the eastern part of the pit is offset and truncated by late stage dykes which, during emplacement, have remobilised mineralisation locally along dyke margins.

The main zone of mineralisation at the Antas North mine has been defined over 350 metres along strike, 300 metres down dip and can be up to 35 metres wide. Extensions of mineralisation along strike and down plunge to the west are considered possible. Economic mineralisation has also been identified near surface at the Azevedo deposit which is located 300 metres from the current Antas North pit limits. Azevedo mineralisation has currently been identified over a 140 metres strike length and a plunging down dip extent of 100 metres to 140 metres. The mineralisation at Azevedo is typically lower grade (~0.8% copper) and thinner (up to 10 metres wide) than mineralisation inside the Antas North pit.

Mining of the Antas North open pit was completed in June 2021. The Company will continue to reclaim and process the remaining surface stockpiles into 2022 as the ramp-up and transition to full Pedra Branca feed occurs. The re-purposing of the Antas North open pit void as a tailings storage facility to support the future Carajás East hub operations has commenced. It will be available for use in 2022.

Processing method: Ore sorting, conventional crushing, grinding, flotation and filtration.

IOCG deposits such as Antas North are amenable for the production of copper and gold concentrates via conventional and well-established flotation routes in the existing plant.

The plant capacity at Antas North is 0.8 Mtpa, used as an assumption for the production plan. Metallurgical assumptions are based on comprehensive metallurgical test work that has been completed for the Antas North deposit and reconciliation results.

Metal recovery estimates are based on actual performance: Copper and Gold recoveries are estimated by equations with the life of mine averaging 97% for Copper and the 84% for Gold, respectively.

The Antas North concentrate typically averages approximately 27% Cu and has low concentrations of deleterious elements (such as As, Bi, F, Hg and U); it is a desirable highquality saleable concentrate on the global market. OZ Miner ........