The Barreiro pegmatite body is emplaced into biotite–quartz schist. Pale greenish–grey coloured, multicentimetre-sized microcrystalline quartz–feldspar intercalations have been noted in the schist, with disseminated green, sub- to one-millimetre-sized amphibole and pink garnet crystals. Pegmatite xenoliths can be found within 3 m of the dike edge within the schist and can range from a centimetre to as much as a metre in size.

The pegmatite strikes northeast–southwest and dips to the southeast at 30–35º. Based on drill data, the dike is about 600 m long, 800 m wide, and has an average thickness of 30–35 m. It remains open to the northeast and at depth. The deepest drill hole reached 374 m. The pegmatite is apparently intruded discordant to the host crenulated biotite schist in surface exposures, but at depth, can be concordant, and emplacement may be related to local fracturing.

The dike is slightly zoned into distinct spodumene-rich and albite-rich areas and is divided into an edge (or border), and a central zone. Overall, spodumene is about 20–24% of the dike mass, albite–microcline is approximately 32–40%, and around 10–18% is mica (muscovite).

The border zone is about 45 cm in thickness, and consists of fine-grained albite, quartz and muscovite. Heavy minerals such as cassiterite and tantalite may occur associated with albite units. The central zone is spodumene-rich and consists of albite and spodumene crystals that are typically 10–25 cm ........

The Barreiro Deposit will be mined by open pit mining methods, using a contracted mining fleet consisting of hydraulic excavators, front-end loaders, and 40t trucks for both waste and ore, coupled with appropriate auxiliary support equipment.

The mine layout and operation are based on the following criteria:
• A single open pit on the Barreiro pegmatite;
• Low height mineralized material benches to reduce mine dilution and maximize mine recovery;
• Pre-splitting of the mineralized material to reduce mine dilution;
• Elevated inter-ramp angles for the waste to reduce strip ratio.

The basis for the scheduling includes:
• Pre-stripping the pit to liberate mineralized material;
• Pit cut-backs in years 4 to 6 to expand and deepen pit;
• Mining at a rate of 1.80 Mtpa;
• The planned open pit mine life is 12 years;
• The mining fleet is based on road trucks and this fleet will be operated by a mining contractor.

At the Barreiro Mine, the mining operations will be carried out by a third-party contractor, with proven experience with similar sized operations in Brazil. In order to select the mining operations contractor, operational work technical specifications were compiled and forwarded to the companies for technical and commercial proposals. After selecting the company and signing a contract, the work of mobilization and construction of the construction site will begin immediately.

The run of m ........

Ore trucked from the mine will be stacked on ROM piles. A Front-End Loader (FEL) will feed material into the crusher feed bin, and an apron feeder will draw the material into the primary crusher. A magnet will remove any tramp metal as the material passes to the scalping screen. The scalping screen undersize material (<9.5 mm) is taken to the DMS feed bin. The oversize material passes to the secondary cone crusher for size reduction. The secondary cone crusher product is joined by the tertiary cone crusher product and directed to a classification screen. The undersize material (-9.5 mm) joins the scalping screen undersize on the DMS feed bin conveyor. The oversize material is conveyed to the tertiary cone crusher feed bin, which splits the material between the two tertiary cone crushers, for size reduction, before it returns to the classification screen.

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