Mineralization at the Santa Luz Project is consistent with an orogenic gold deposit type. orogenic gold deposits are distributed along major compressional to transpressional crustal-scale fault zones, in deformed greenstone terranes commonly marking the convergent margins between major lithological domains, such as volcano-plutonic and sedimentary domains.

Greenstone gold deposits are structurally controlled, epigenetic deposits characterized by simple to complex networks of gold-bearing, laminated quartz-carbonate fault-fill veins. These veins are hosted by moderately to steeply dipping, compressional, brittle-ductile shear zones and faults with associated extensional veins and hydrothermal breccias. These deposits are hosted by greenschist to locally amphibolite-facies metamorphic rocks of dominantly mafic composition and formed at intermediate crustal depth (5 km to 10 km). The mineralization is syn- to late-deformation and typically post-peak greenschist-facies or syn-peak amphibolite-facies metamorphism. It is typically associated with iron carbonate alteration. Gold is largely confined to the quartz-carbonate vein network; however, it may also be present in significant amounts within iron-rich sulphidized wall rock selvages or within silicified and arsenopyrite-rich replacement zones. In the Project area, gold deposits are hosted within the Paleoproterozoic aged RIGB, which was deformed and metamorphosed during the Trans-Amazon Orogeny (approximately 2 Ga). Gold mineralization mainly occurs with fault-related quartz-sulphide and quartz-carbonate-sulphide veining and quartz-sulphide breccia. Alteration includes sericitization, carbonate alteration, albitization, sulphidation, and silicification.

There are two main types of quartz veins. The most common type is foliation-parallel, white to grey coloured, north–south striking, and generally <1 m wide. These may be deformed and boudinaged, or may appear undeformed. Where deformed, they are associated with stretch lineations related to transcurrent or thrust movements. The second type of commonly observed quartz vein is most likely related to late northeast-striking structures. These structures are in brittle or ductile-brittle faults that crosscut all other structures, including foliation, and display a general dextral sense of movement. The veins associated with these structures are normally black or dark grey, and are thicker than the north-south striking veins. Fluid assisted hydraulic breccia is commonly associated with these veins.

Mixed veins, characterized by black and milky-coloured quartz, are found in strongly broken zones, mainly at the intersections of the north-south structures with the northeast-southwest structures. These intersections host voluminous and high-grade gold quartz veins and silicified breccia. The host rocks of the gold mineralization exhibit weakly to moderately strong hydrothermal alteration. The most common type is quartz-sericite alteration. Also common are locally-pervasive albitization, carbonatization, and sulphidation.

Mineralized zones range in thickness from a few metres to tens of metres and have relatively long strike and dip lengths. Mineralization at C1 has a north-south strike length of approximately 1,550 m, width of approximately 1,400 m orthogonal to strike, and a depth extension of at least 840 m. Mineralization ranges in thickness from 15 m to 55 m with good continuity along strike and down dip.

Dacitic mineralization accounts for approximately 45% of the deposit, with carbonaceous mineralization accounting for 55% of the deposit.

Mineralization at Antas 3 has a north-south strike length of approximately 1,575 m, width of approximately 200 m to 400 m orthogonal to strike, and depth extension of 150 m. Mineralization ranges in thickness from <5 m to 15 m with good continuity along strike and down dip. Dacitic mineralization accounts for approximately 67% of the deposit, with carbonaceous mineralization accounting for 33% of the deposit. Mineralization for C1 and Antas 3 is open at depth beyond the current limits of drilling and along strike, although it becomes relatively weaker.

QEMSCAN analysis found that gold is mainly found in association with pyrite and arsenopyrite as fine-grained inclusions, on grain boundaries and on fractures of sulphide grains. Gold grains may also be found in and on the surfaces of gangue minerals, especially hydrothermal quartz or carbonate. Gold grains commonly range from <5 µm to over 30 µm in size, with increasingly rare occurrences at progressively larger sizes.

Santa Luz will be an off-highway truck and excavator open pit mining operation. The ore and waste rock will be drilled and blasted, loaded onto trucks, and then hauled to the crusher area, stockpile areas or waste dumps.

The new pit slopes are comparable to the pit slopes recommended by VogBR (2014). The pit designs follow these recommendations and are based on a total bench height of 10 m.

A minimum mining width of 20 m was used for the pit designs. This width ensures safe loading and hauling.

Mining operations will consist of: waste rock stripping and overburden removal; drilling and blasting; and loading and hauling of ore and waste. Ancillary activities will include: road maintenance; site dewatering; waste dump and stockpile maintenance; and grade control.

The crushing section of the plant is part of the original facility. It consists of a jaw crusher followed by a cone crusher, both of which are in open circuit, with the product conveyed to a conical stockpile.

Run-of-mine ore is fed by a front-end loader, from stockpiles on a pad adjoining the crushing plant, and into a hopper in front of the jaw crusher. Ore is withdrawn from the hopper by a vibrating feeder-grizzly, with grizzly oversize feeding the jaw crusher and grizzly undersize dropping to a conveyor that transports the grizzly undersize and the jaw crusher product to a transfer hopper, thence to a second conveyor that feeds a cone crusher. Prior to entering the grinding circuit, a third conveyor takes the crushed ore from the secondary crusher to a crushed ore stockpile.

The grinding section will consist of two mills: a SAG mill and a ball mill operated in series. The SAG mill was part of the original facility; the ball mill is new. The SAG mill, as originally installed, operated as a single-stage SAG mill to produce the final grind size. The new ball mill is a conventional overflow ball mill, and will grind the SAG mill product to the final grind size.

Ore from the stockpile is drawn by two underlying vibrating feeders onto the SAG mill feed conveyor. The SAG mill is equipped with a trommel screen that screens out plus 12 mm pebbles. The pebbles are conveyed back to the SAG mill feed conveyor and are expected to constitute approximately 5% of new feed. Trommel screen undersize will be pumped via new pumpsto the new primary mill cyclones; cyclone underflow will be recycled to the SAG mill, and the cyclone overflow will pass to the ball mill discharge pump box. From the ball mill on, all process equipment is new. The ball mill discharge pumps (one operating, one spare) will pump the combined SAG mill cyclone overflow and the ball mill discharge to the secondary mill cyclones. Cyclone underflow flows to the ball mill feed. Dry lime will be fed from a silo adjoining the ball mill pump box directly into the pump box. Cyclone overflow will flow to a trash screen. Trash screen oversize will be recycled to the ball mill pump box; trash screen undersize will flow to the plant feed sampler and thence to a pump box from which it will be pumped to the RIL circuit.

The original processing plant at Santa Luz was built and placed in operation in mid-2013 and was shut down in September 2014 after 14 months of operation. The plant did not operate well, as a result of both process difficulties and mechanical problems. The new processing facility will incorporate the crushing, crushed ore storage, and SAG mill sections of the original plant. The rest of the plant, with the exception of the refinery, will be new.

The new processing facility will incorporate the crushing, crushed ore storage, and SAG mill sections of the original plant. The rest of the plant will be new, except the refinery. The new facility will process a blend of carbonaceous and dacitic ore, using the following processing sequences:
- Two-stage crushing
- Two-stage grinding
- Gravity concentration and intensive cyanidation
- Pre-aeration and kerosene conditioning
- RIL
- Detoxification of leached tailings
- Containment of tailings in a T ........