The main deposit type in the Aurizona project area is greenstone-hosted orogenic gold, a subtype of the larger orogenic class of gold deposits. Greenstone-hosted orogenic gold deposits are structurally controlled epigenetic deposits. Gold occurs in networks of laminated quartz-carbonate fault-fill veins hosted in moderately to steeply dipping, brittle-ductile shear zones and faults, with locally associated extensional veins and hydrothermal breccias. Most of these deposits are hosted by meta-mafic rocks of greenschist to locally lower amphibolite facies and formed at depths of 5 - 10 km. The relative timing of mineralization is typically syn- to late-deformation and syn- to post-peak metamorphism. They are formed from low salinity, H2O- and CO2-rich hydrothermal fluids with typically anomalous concentrations of CH4, N2, K, and S. Gold may also occur outside of veins within iron-rich sulphidized wall rock. Orogenic gold systems are typically associated with deep-crustal fault zones that mark the convergent margins between major lithological blocks.

The main ore mineral is native gold that is typically associated with pyrite, pyrrhotite, and/or chalcopyrite, along with trace amounts of molybdenite and telluride in some deposits. Arsenopyrite commonly represents the main sulphide phase in amphibolite-facies rocks, and in deposits hosted by clastic sediments. Sulphide minerals generally constitute less than 10%, and typically less than 5%, of the volume of the ore bodies and exhibit little vertical zoning. The main gangue minerals are quartz and carbonate, with variable amounts of white mica, chlorite, tourmaline, and locally, scheelite. Gold-bearing veins are typically enveloped by alteration halos that in greenschist-facies rocks, grade outwards from iron-carbonate + sericite + sulphide (pyrite ± arsenopyrite) assemblages to various amounts of chlorite, calcite, and locally, magnetite. The dimensions of these alteration haloes vary with the composition of the host rocks and may envelop entire deposits hosted by mafic and ultramafic rocks. Pervasive chromium- or vanadium-rich green micas (fuchsite and roscoelite) and ankerite with zones of quartz-carbonate stockwork are common in sheared ultramafic rocks. Hydrothermal assemblages associated with gold mineralization in amphibolite-facies rocks include biotite, amphibole, pyrite, pyrrhotite, and arsenopyrite; at higher grades they include biotite/phlogopite, diopside, garnet, pyrrhotite, and/or arsenopyrite with variable proportions of feldspar, calcite, and clinozoisite. The variations in alteration styles have been interpreted as a direct reflection of the depth of formation of the deposits.

Significant gold occurrences in the project area include the Piaba, Boa Esperança, and Tatajuba deposits, as well as the Genipapo, Mestre Chico, and Micote targets. Each of these is briefly described below.

PIABA
Piaba is a structurally-controlled, tabular, orogenic gold deposit with a strike length of ~3.3 km, width of 10 – 50 m, and down-dip extent of at least 600 m, beyond which the deposit is sparsely explored. The deposit is hosted in the brittle-ductile Aurizona shear zone (ASZ) that is ENE-WSW striking and steeply north dipping to the NNW.

Within the Piaba deposit, the ASZ system is divided into ten shear zones and/or brittle faults, partially segmenting the deposit with limited offsets. The maximum offset observed is 100 m, whereas most offsets are in the order of 10 m. The most significant of these structures is the Pirocaua fault zone at the east-northeast end of the deposit. This brittle fault zone is up to 350 m wide and locally disrupts the Piaba gold zone (maximum offset 75 m). At the western end of Piaba on section 1900W there is a northwest striking fault, that truncates the gold zone at depth.

Mineralization is primarily hosted in the quartz diorite that is also described as a dike-like c.2.0 Ga granophyric granodiorite (e.g. Freitas and Klein, 2013; Klein et al., 2015) but has also been interpreted as a cataclastic unit. Ore-related alteration includesstrong to intense sericite-carbonate-silica-sulphide alteration in the central part of the structure (i.e. in the quartz diorite) flanked by chlorite-dominant alteration in the foot and hanging walls. Gold is mostly hosted in thin, millimetre to centimetre-scale, and quartz -carbonate ± sulphide± tourmaline bearing shear veins. Native gold is rarely observed at wall rock-vein contacts. Sub- horizontal quartz-carbonate extensional veins commonly cut shear veins and can contain gold. Increased vein density and sulphide abundance are the best indicators of gold mineralization.

BOA ESPERANCA
The Boa Esperança deposit is located approximately one kilometre southwest of the Piaba deposit and consists of two to four sub-parallel gold-bearing zones that are continuous along strike for ~1000 m. The five gold-bearing zones are each about 5 ± 2 m wide and developed in a corridor ranging from 40 – 75 m in width, narrowing to 20 m at the northeastern end where there are generally just two to three zones. The deposit extends to at least 230 m below the surface and is hosted within a brittle-ductile structure trending ENE-WSW and dipping steeply (80°–90°) to the NNW. Mineralization is hosted in strongly altered and deformed Aurizona Group rocks, likely derived from the adjacent Aurizona Group diorite gabbro and/or sedimentary rocks. The mineralized corridor shows strong silica-sericite-albite-carbonate alteration, along with increased disseminated pyrite (2 – 5 modal%) and density of quartz-carbonate-sulphide veins.

TATAJUBA
The Tatajuba deposit is also hosted within the ASZ, with the eastern end of the deposit located ~2 km west of the western end of the Piaba deposit. The Tatajuba deposit comprises a tabular zone that is east-west striking and steeply north-dipping; the zone measures ~700 m long, 5 – 30 m thick and 300 m in downdip extent. Within the eastern portion of the Tatajuba deposit, the ASZ system isinterpreted to be cross-cut by subvertical NNW-trending structures. The maximum offset observed is between sections 200E and 300E, where the deposit is offset by 10 m, through sinistral shearing and/or faulting. Gold mineralization is hosted in a steeply north dipping quartz diorite unit with concordant shear veins and moderately south dipping extension veins. The quartz diorite shows granular cataclastic texture and issilica-carbonate-sericite-altered, grading outward into strongly chlorite-carbonate-altered rocks. Shear and extension veins are mostly restricted to the tabular quartz diorite unit, with shear veins sub-concordant to this unit and consisting of quartz ± carbonate ± chlorite ± pyrite ± arsenopyrite. Extension veins appear to be moderately south dipping to sub-horizontal and consist of quartz with ~1–10% pyrite. Visible gold occurs in both vein types but is most abundant within the extension veins. Gold values are correlated with arsenic, carried by arsenopyrite.

MICOTE
The Micote target lies ~2.4 km due east of the eastern end of the Piaba deposit and consists of at least two,sub-parallel, mineralized zones that both strike ENE to E-W and dip steeply (75°–80°) to the north. Mineralization occurs along 300 m of strike length but is discontinuous (individual zones range around 110 – 175 m in length). Both mineralized zones are 10 – 15 m wide and are defined to depths of 60 and 130 m below the surface. Mineralized zones are hosted in a tightly intercalated sequence of diorite, intermediate volcaniclastic, ultramafic, gabbro, argillite, and muscovite schist, with many of these units ranging from 5 – 25 m in thickness.

MESTRE CHICO
The Mestre Chico target lies 2 km ENE of the eastern end of the Piaba deposit. Mineralization is restricted to a single drill section and is either discontinuous or developed on an atypical trend. It is therefore not possible to comment on zonal dimensions or orientation.

The Aurizona Mine is an operating open pit mine with ore processing by gravity concentration and cyanide leach/CIP circuit. Current mine production is a nominal 8.1 million tonnes per year for a plant feed rate of 2.92 million tonnes per year. For 2019, gold production was 86,000 ounces to the mill.

Highwall slope angle criteria vary by area and pit. In general, the interramp angles vary from 33 to 60 degrees depending on pit area and wall orientation. This is due to a foliation that is present parallel to the walls in certain zones.

Heights between safety benches vary by material type. In the saprolite and transition zone the benches are placed each 6 metres while in the fresh rock they are placed each 18 metres. Berm widths vary from 3.5 metres to 9.0 metres depending on the zone. Every 54 metres vertically in saprolite and transition zones, a 10-metre berm is required.

A larger catch berm of 20 metres is in the design at the -44 level which roughly represents the base of the transition zone. This is expected to be a dewatering zone for the slope due to the higher permeability of the material.

Three pit areas are considered:
1) Piaba – 8 phases
2) Piaba East – one phase
3) Boa Esperança – one phase

The mine schedule utilizes the pit and phase designs to send a peak of 3.2 million tonnes of ore to the plant in 2021 then lesser amounts in the following years. This peak is possible due to the higher percentage ofsaprolite which allows a slight increase in plant throughput. Total mine production peaks at 34.9 million tonnes in 2020 then declines as the mine advances.

Haulage profiles were determined for each phase by year to determine the proper mine equipment is available to meet mine schedule and ensure no shortfall in equipment is present. The mine equipment is sufficient to meet the production schedule.

Mining in 2020 will complete the East Piaba pit, and Piaba phases 2 and 3.

In 2021, the Boa pit will be started and completed in the same year. Piaba phase 1, 4, and 5 will be finished. Piaba Phase 6 will be started in 2021. Phase 7, both A and B, will be initiated in 2022 together with Phase 6. Phase 7A is primarily a ramp access phase to assist in the waste haulage from Phase 7, while minimizing the overall pit size. Phase 6 is completed in 2023 and Phase 7 continues until the end of the mine life in 2026.

Primary Crushing
The crushing facility crushes ROM ore at an average processing rate of 392 t/h. The major equipment and facilities at the ROM receiving and crushing area include:
- Stationary grizzly with 700 mm spacing bars.
- 120m3 ROM surge bin.
- Apron feeder.
- Vibrating grizzly feeder.
- Jaw crusher (Metso C120 type) with a 160 kW motor.
- SAG mill feed surge bin feed conveyor with beltscale.
- Dustsuppressing system.

The ROM ore is trucked from the open pits and dumped directly into the ROM surge bin or stockpiled on the ROM storage pad and then reclaimed by a front-end loader to the ROM surge bin. The ore in the ROM surge bin is reclaimed by an apron feeder.

The ROM ore is then fed onto the vibrating grizzly feeder where the screen oversize is directed to the jaw crusher. The jaw crusher crushes the ore to a P80 of approximately 120 mm. The crushed ore reports to the surge bin feed conveyor which also receives the vibrating screen undersize material (~44% of the ROM ore). The combined crushed ore and the screen undersize is conveyed to the SAG mill feed surge bin.

The ore receiving and primary crushing areas are equipped with a dust suppressing spraying system to control fugitive dust generated during ROM ore feeding, screening, crushing and conveyor loading.

Mill Feed System
The coarse ore stockpile and mill feed system include:
- Mill feed surge bin.
- Surge bin apron feeder.
- SAG mill feed conveyor.
- Front-end loader reclaim

The SAG mill feed surge bin has a live capacity of 10 minutes (45m3). The crushed material is reclaimed from the surge bin by an apron feeder at a nominal rate of 362 t/h onto a belt conveyor to feed the SAG mill. During crusher operation, the surge bin feed rate exceeds the discharge rate and feed can be diverted from the bin. The diverted ore is conveyed to an emergency stockpile for reclaim by FEL during crusher or ROM feed outages. The crushed ore dead stockpile is designed to have 30 hours of storage.

Grinding
The grinding circuit consists of a SAG mill in open circuit with a small pebble recycle stream and a ball mill in closed circuit with cyclones. The nominal feed rate to the SAG mill is 362 t/h.

The grinding circuit includes:
- SAG mill; 8.5m diameter by 4.0m long EGL, driven by a 5,300 kW variable frequency drive (VFD).
- Ball mill; 5.5m diameter by 7.4m long EGL, driven by a 3,800kW fixed speed drive.
- Cyclone feed pump box and one installed cyclone feed pump.
- 50 m3 cyclone feed pump box and two cyclone feed slurry pumps.
- Cyclone cluster ofsix 600 mm cyclones.

The crushed ore from the surge bin is reclaimed onto the SAG mill feed belt conveyor that feeds the ore to the SAG mill. The SAG mill discharge is screened by a short trommel screen that is integrated with the SAG mill. The trommel screen has an opening of 10mm (slot width). Steel balls are manually added into the SAG mill on a batch basis as grinding media.

One magnet and one metal detector are provided to remove and detect any metal. A pebble crusher
installation is planned for the future.

The SAG mill trommel undersize and the product from the ball mill discharges by gravity into the cyclone feed pump box where the slurry is pumped to the cyclones for classification. The cyclone underflow returns to the ball mill, creating a circulating load to the ball mill of approximately 250%. The cyclone overflow with a P80 of 100 µm flows by gravity to the pre-leach thickener prior to subsequent cyanidation treatment. The pulp density of the cyclone overflow is approximately 32% w/w solids. Steel balls are manually added into the ball mill on a batch basis as grinding media.

Dilution water is added to the grinding circuit as required. Lime is added to the SAG mill to maintain a slurry pH of 10.5 or higher.

The grinding mills have 9.1 MW of total installed grinding power providing sufficient power for the duty feed rate at the predicted feed blends in the LOM plan. The design power of the grinding mills provides for up to 85% harder fresh rock feed. During times when the feed contains less than 50% of the harder fresh rock material the comminution circuit can handle a higher throughput without sacrificing grind size. The grinding circuit has been operating at 390 t/h and approximately 91% effective availability since start-up in May 2019. Excluding scheduled maintenance, the grinding circuit is typically operating at over 9,000 t/d.

The Aurizona Mine was placed on care and maintenance status in late 2015 and had operated successfully for over 4 years prior to that. The process plant was subsequently upgraded during 2018-2019, mining resumed in 2019 and Aurizona achieved commercial production July 1, 2019. The process plant now consists of the following main processing facilities with a nominal processing rate of 8,000 t/d:
- primary crushing and associated material handling equipment;
- crushed ore surge bin, emergency stockpile, associated feed and reclaim systems;
- grinding circuit, including a SAG mill, ball mill, and associated pumping and material handling systems;
- a gravity circuit with intensive leach reactor, an electrowinning cell and associated equipment;
- cyanide Leach/CIP circuit and associated gold recovery and carbon handling circuits, including; pre-leach thickening, leach and CIP tanks, acid wash and elution, carbon reactivation, gold electrowinning and smelting;
- ........