The Project lies within the north to south trending Neoproterozoic Araguaia Fold Belt.

The belt comprises metamorphosed and deformed marine-clastic sediments of the Tocantins Group and is split into two formations based on the degree of metamorphism present. The prospective areas of HZM are located in the western Couto de Magalhães Formation which contains weakly metamorphosed, marine pelites with local carbonate, iron-rich, and mafic to ultramafic bodies.

The local geology has largely been interpreted from airborne geophysical survey data, soil sampling data, mapping and core drilling by HZM and previous owners of the tenements. Various types of metasediments cover the vast majority of the licence area. Large plateau areas, varying in size from a few hundred square metres to several square kilometres, and generally capped with a hard iron-rich duricrust that is occasionally silicified are frequently developed over mafic and ultramafic bodies. These bodies and numerous northwest-southeast to north-south trending lineaments have been identified from magnetic data and outcrop. These bodies are often bounded by a siliceous breccia. Bodies of pillow lava and other volcanic material also exist. The area is cut by numerous mafic dykes.

A distinctive lateritic sequence is developed over ultramafic and mafic rocks within the Project area and the same sequence can be recognised at each of the target sites though the thickness and extent of each facies varies from location to location. The sequence can be split into six main facies types: soil, ferricrete, limonite, transition, saprolite and fresh rock, as well as numerous sub-facies.

The Project can be divided into Araguaia Nickel North (ANN) and Araguaia Nickel South (ANS). The ANN section comprises the Vale dos Sonhos (VDS) deposit. ANS comprises the following deposits:
- Jacutinga (JAC)
- Vila Oito West (VOW)
- Vila Oito (VOI)
- Vila Oito East (VOE)
- Pequizeiro (PQZ)
- Pequizeiro West (PQW)
- Baião (BAI)

The target mineralisation of the Project area is characteristic of typical nickel laterite deposits formed in a seasonally wet tropical climate, on weathered and partially erpentinised ultramafic rocks. Features of nickel laterites include:
- The nickel is derived from altered olivine, pyroxene and serpentine that constitute the bulk of tectonically emplaced ultramafic oceanic crust and upper mantle rocks.
- Lateritisation of serpentinised peridotite bodies occurred during the Tertiary period and the residual products have been preserved as laterite profiles over plateaus/amphitheatres, elevated terraces and ridges/spurs.
- The process of formation starts with hydration, oxidation, and hydrolysis, within the zone of oxidation, of the minerals comprising the ultramafic protore.
- The warm/hot climate and the circulation of meteoric water (the pH being neutral to acid and the Eh being neutral to oxidant) are essential to this process. Silicates are in part dissolved, and the soluble substances are carried out of the system.
- This process results in the concentration of nickel in the regolith in hydrated silicate minerals and hydrated iron oxides; nickel and cobalt also concentrate in manganese oxides. The regolith hosting nickel laterite deposits is typically 10 m to 50 m thick, but can exceed 100 m.
- Concentration of the nickel by leaching from the limonite zone and enrichment in the underlying saprolite zones is also common. Leaching of magnesium +/- silicon causes nickel and iron to become relatively concentrated in the limonite zone. Nickel is released by recrystallisation and dehydration of iron oxy-hydrides and is slowly leached downwards through the profile, both vertically and laterally, re-precipitating at the base with silicon and magnesium to form an absolute concentration within the saprolite.
- The degree of the nickel concentration and the detailed type of regolith profile developed is determined by several factors including climate, geomorphology, drainage, lithology composition, and structures in the parent rock, acting over time.
- A typical laterite profile contains three distinct horizons (limonite, transition and saprolite).

Planned mining at ANP is to be completed with conventional open pit truck and excavator mining methods. No blasting will be necessary. The orebodies are flat lying and variable in composition. Waste overburden will be stripped on 4 m benches, and ore on 2 m benches for additional selectivity.

Reverse circulation (RC) grade control drilling will be completed at 10 m x 10 m spacing to define the waste/ore/ore type boundary ahead of mining. In addition, visual control at the boundary of the limonite and the transition ore will be used to minimise the amount of limonite being included in the ore feed.

Waste will be stored in external dumps nearby the pits. Ore will be transported to stockpile hubs near each deposit. Sheeting (using ferricrete won from the overburden) will be required to support trafficability in and around the mine during the wet season. Depending on plant demand, ore will be hauled from hub stockpiles or directly from the pits to the run of mine (ROM) at the RKEF process facility. Stockpiles on the (ROM) will be sheeted and classified according to ore type and chemistry for blending.

Due to the high rainfall in the wet season, mining (including stockpile rehandling) will be restricted to the Pequizeiro area between October and March. Mining rates are approximately three times higher in the dry season, which is typical in Brazilian open pit mining operations.

The annual mining rate peaks at 3.5 Mt/a between production years 2 and 7 before dropping down to 3.0 Mt/a for the remainder of the Project.

The equipment deployed on the mining operations will be dependent on the mining contractor awarded the work.

The Project comprises a planned open pit nickel laterite mining operation that mines a 27.5 million tonne (Mt) Mineral Reserve of a 119 Mt Mineral Resource to produce 52,000 tonnes of ferronickel (FeNi) (containing 14,500 tonnes of nickel) a year.

After an initial ramp-up period, the plant will reach full capacity of approximately 900,000 tonnes per annum (t/a) of dry ore feed.

The Project will utilise a single rotary kiln electric furnace (RKEF) processing line from ore receipts through to shotting of the FeNi product. The product is a FeNi alloy having a 30% Ni content.


The key steps in the RKEF flowsheet are:
- ROM ore, at an average moisture content of 34%, is first blended to meet metallurgical processing requirements, then transported to the primary crushing stage. Here the ore is sized using two stages of crushing to match the requirements of the subsequent steps. A mineral sizer with a 200 mm gap is used for primary sizing, while a mineral sizer with a 50 mm gap is used for the final stage.
- The ore is then homogenised, partially dried and agglomerated to an average moisture content of 18% in a rotary dryer (4.5 m diameter x 40 m long) and fired with pulverized coal.
- The dried agglomerated ore is then fed to the rotary kiln with the addition of reductant coal. In the kiln, the ore is completely dried, calcined to remove chemically-combined moisture, and the iron and nickel oxides are partially pre-reduced. Drier and rotary kiln dusts are recycled to the agglomeration process before the primary crushing stage ahead of the dryer.
- Calcine from the kiln is then transferred to the electric furnace where further reduction of the nickel and some of the iron is achieved, melting and separation of the metal and slag occurs at high temperature. Slag is tapped at a temperature of around 1,575°C, while FeNi metal is tapped at a temperature of close to 1,500°C.
- After tapping, the melt is transferred by ladle to the refining stage. The final FeNi product containing 30% Ni is shotted with water, screened, dried and stockpiled prior to dispatch to the port on trucks where it either bagged or loaded bulk into sea containers for shipping to customers.
- The electric furnace slag is granulated and transferred to the slag repository by truck.