The Aurizona Property mineralization is characterized as a greenstone-hosted orogenic gold system. Mineralization occurs as structurally-controlled gold deposits including the Piaba deposit, which is currently being mined. Piaba, Boa Esperança, Tatajuba and Genipapo deposits are on and adjacent to the Aurizona Shear Zone (ASZ), a regional northeast-striking structure. Touro is 16 km southwest of the Aurizona Mine which hosts gold mineralization within an intrusive unit. These deposits are hosted by Paleoproterozoic volcano-sedimentary and intrusive rocks of the São Luis Craton, an eastern extension of the Guyana Shield which contains several major Proterozoic gold deposits including Las Cristinas, Omai, and Rosebel, extending from Venezuela to Brazil.

The Property geology is dominated by volcano-sedimentary sequences of the 2.23-2.24 Ga Aurizona Group (Klein et al, 2015), and granitoids of the Tromaí Intrusive Suite. The Aurizona Group is comprised of felsic, intermediate, and mafic volcanic and volcaniclastic rocks, as well as metasedimentary rocks. The bedrock units are covered by Phanerozoic sedimentary basin deposits and recent coastal sediments.

Gold mineralization at Piaba and the other deposits is generally associated with subvertical tabular zones of intense shearing and hydrothermal alteration consisting of quartz-carbonatesericite±chlorite. Quartz±carbonate shear veins are the primary host for gold mineralization with flat to shallow dipping quartz±carbonate extensional veins also carrying gold. Pyrite is the dominant sulphide with lesser arsenopyrite or pyrrhotite, except at Tatajuba and Touro where arsenopyrite mineralization is commonly observed. Native gold is observed within the grey shear veins, commonly occurring along vein margins.

An aerially extensive regolith profile has developed across the Property with distinct effects on geochemical dispersion and physical properties within each regolith domain type. The regolith profile overprints mineralization and can extend to vertical depths of more than 60 m, and is underlain by fresh, sulphide-bearing rocks that host primary gold mineralization.

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 700 m, beyond which the deposit is sparsely explored. The deposit is hosted in the brittle-ductile 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 Pirocaua fault zone at the east-northeast end of the deposit is a significant structure. This brittle fault zone is up to 350 m wide and locally disrupts the Piaba gold zone with a maximum offset of 75 m. At the western end of Piaba on section 1900W there is a northwest striking fault, which truncates the gold zone at depth. Near surface mineralization continues west of the fault in Piaba west area although the possible offset of the mineralization at depth has not been tested.

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 cataclasite unit. Ore-related alteration includes strong 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 footwall and hangingwall. Gold occurs 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 Esperança
The Boa Esperança deposit is located approximately one kilometre south of the Piaba deposit and consists of four sub-parallel gold-bearing zones that are continuous along strike for ~1000 m (Figure 7- 5). The four 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 zones. The four gold bearing zones coalesce within the saprolite and laterite portions of the eastern margin of the deposit. 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 minor metasedimentary rocks. The mineralized corridor shows moderate to strong silica-sericite-albite-carbonate alteration, along with increased disseminated pyrite (2 – 5 modal percent) 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 is interpreted 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.

Genipapo
The Genipapo North and South deposits are located about one kilometre east of the eastern margin of the Piaba deposit, with Genipapo North approximately 400 m north of Genipapo South. These deposits form in splays off the ASZ. The geology, geochemistry and magnetic data indicate a horsetail structure off the ASZ structure. Numerous fault structures and discontinuous splays of metavolcanoclastic and ultramafic units have been interpreted at Genipapo and the surrounding area. The metavolcaniclastic sequences are comprised of metatuffs, metagraywackes, phyllites and are in fault contact with ultramafic rocks. Gold mineralization is associated with shear-hosted smoky quartz veins and millimetre-scale extensional veins that form a stockwork. The mineralization forms in quartz ± albite ± sericite alteration with pyrite and arsenopyrite minerals. There is a strong correlation between gold and arsenic.

Touro
Touro is located about 20 km southwest of the Piaba deposit. The Touro deposit is hosted in a coarsegrained DRT and strongly deformed MVC rocks from Aurizona Group. A regional northeast-southwest treading mylonitic shear zone the host rocks which are cut by late andesite and aplite to pegmatite dykes.

The mineralized zone trends 340° and is 600 m long, 130 m thick and roughly 150 m depth extents. Gold mineralization is hosted in albite altered diorite (ADT) with extensional quartz veins system. The ADT unit shows equigranular texture and is composed of albite-silica-sulfide (pyrite ± pyrrhotite ± sphalerite). Extensional veins are the most abundant vein type, composed of quartz ± pyrite ± chlorite ± carbonate that are moderately south dipping to sub-horizontal. Visible gold occurs in both extensional and shear vein types. Gold values are associated with sodium alteration (albite) zones.

The Aurizona Mine is an open pit operation using conventional mining equipment. Open pit mining is being completed by a local Brazilian contractor. The Life-of-Mine (LOM) plan includes the addition of underground mining beneath the Piaba pit that assists in extending the mine life to 2032.

The mine schedule is based on 2021 reserves using the Piaba, Piaba East, Boa Esperança, Tatajuba, and Genipapo pit areas plus the Piaba Underground. It totals 32.3 Mt of proven and probable ore grading 1.60 g/t gold to the process plant over a current design life of 11 years. The ore tonnage is made up of 16.6 Mt of proven reserves grading 1.39 g/t gold and 15.7 Mt of probable reserves grading 1.82 g/t gold and includes 0.3 Mt of proven ore at 0.92 g/t gold currently in the stockpile from 2021 mining activity. Waste tonnage totals 96.9 Mt to be placed in the various waste rock management facilities. The overall strip ratio is 3.79:1 mined.

Highwall slope angle criteria vary by area and pit. Previous slope study work by third party consultants remains valid and was used in the update of the pit designs. The slope information from Piaba was applied to Tatajuba and Genipapo due to similar lithology and weathering profiles.

In general, the inter-ramp angles vary from 33 to 60 degrees depending on pit area and wall orientation. This is due to foliation present parallel to the walls in certain zones.

Five open pit areas are considered in the reserves statement: Piaba (4 phases), Piaba East, Boa Esperança, Tatajuba (2 phases), and Genipapo (2 pit areas each with 1 phase). The Boa Esperança open pit will become a freshwater storage facility once excavated.

Underground mining beneath the Piaba open pit will be accessed with a portal located in fresh rock at the western end of the Piaba pit. The main ramp will initially be a single decline for the first 735 m where it will connect with the main return ventilation raise and utilidor/emergency egress. From there the ramp will become a twin development with the second decline designated as the return air decline for ventilation. This method avoids the need for costly ventilation raises through laterite, saprolite and transition materials.

The initial access will be used to for exploration, geotechnical data collection and training purposes while the mining permit is in process, then transitions to the production ramp once mining commences. The final ramp will access the seven underground zones outlined as part of the mine plan and comprising the reserves over its 2 km length from the portal. Additional development for each of the zones will come off the main ramp.

The method employed will be longhole mining with a 23 m sub-level vertical interval and will use either a permanent rib pillar or cemented rockfill. The use of cemented rockfill has been allocated to the crown pillar area and stopes with widths exceeding 8 m due to geotechnical considerations. A 28 day curing period has been included in the mine schedule for cemented stopes. The other stopes will use a permanent rib pillar with uncemented rock backfill. The percentage of stopes with rockfill is 83% while the percentage requiring cemented rock fill is 17%.

Underground production is expected to begin in the last quarter of 2023. The daily mining rate is expected to increase to 580 t/d by the end of 2024 and be at 2,700 t/d at the end of 2025. Underground mine production will maintain a daily rate above 3,100 t/d from 2026 until the middle of 2029 at which time daily production will decline until the mine is exhausted in mid-2031.

Underground mine infrastructure includes a utilidor raise to surface, dewatering system, power distribution, communications, underground workshop, fuel and lube supply, hydraulic bulkheads for crown pillar removal, and temporary explosive storage.

Primary Crushing
ROM is trucked from the open pits and dumped directly into the crusher feed bin or stockpiled on the ROM storage pad and then reclaimed by a front-end loaderto the 120 m3 ROM bin. The ore is reclaimed by an apron feeder.

The ROM is fed onto the vibrating grizzly feeder where the screen oversize is directed to the jaw crusher (Metso C120 type with a 160kW motor). The jaw crusher crushes the ore to a P80 of approximately <120 mm. The crushed ore, along with the vibrating screen undersize material, is conveyed to the SAG mill feed surge bin.

Mill Feed System
The SAG mill feed surge bin has a live capacity of 9 minutes (45 m3). The crushed material is reclaimed from the surge bin by an apron feeder onto a belt conveyor to feed the SAG mill. During crusher operation, the surge bin feed rate exceeds the discharge rate, and the feed is 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 has 30 hours of storage capacity.

Grinding
The grinding circuit consists of a SAG mill (8.5 m diameter x 4.0 m EGL with a 5,300 kW variable frequency drive) in open circuit with a small pebble recycle stream and a ball mill (5.5 m diameter x 7.4 m EGL with a 3,800 kW fixed speed drive) in closed circuit with cyclones.

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 and ball mill on a batch basis as grinding media.

One magnet and one metal detector are provided to remove and detect any metal.

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 75 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.

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. During times when the feed contains less than 50% of the harder fresh rock material the comminution circuit can handle a higher throughput, up to 10,000 t/d or higher, without sacrificing grind size. A pebble crusher, which was deferred from the original mill upgrade in 2019, is expected to be installed in 2022 to handle an increasing portion of fresh rock.

The Aurizona process plant currently treats the ore via a conventional cyanidation process. Runof-mine (ROM) ore is processed using a conventional primary crusher and SAG-Ball mill comminution circuit followed by gravity circuit, CIL process and associated gold recovery and carbon handling circuits to produce gold doré.

The process plant was upgraded during the recent construction project in 2018-2019 and recommenced operations in May 2019. The process plant was upgraded to treat 8,000 t/d ore (2.9 Mt/a) based on a blend of laterite/saprolite, transition and fresh rock. The process plant has been generally treating ore feed grades nominally ranging from 1 g/t to 2 g/t, mainly saprolite and transition ore blends, and achieving approximately 90.5% average recovery. The process plant is not expected to require any major modifications with the mine expansion plans, including the Piaba underground, however the installation of a new pebble crusher in planned for 2022 as higher per ........