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June 11, 2021 - Aya Gold & Silver Inc. (TSX: AYA) (“Aya” or the “Corporation”) is pleased to announce closing of the previously announced acquisition of Algold Resources Ltd.
Aya Gold & Silver Inc. controls 100% of Algold Resources Ltd and is the 75% owner-operator of Tijirit Gold Project, with the remaining 15% owned by the Government of Mauritania and 10% by Wafa Mining & Petroleum.
The Algold’s operating subsidiary is the Société Tijirit Exploitation SA (Tirex S.A.) (formerly known as Société Tijirit Recherché et Exploration SARL), incorporated to operate the Tijirit and East Tijirit licenses.
Deposit Type
- Banded iron formation
- Vein / narrow vein
Summary:
Tijirit project is located approximately 40 km southeast of the Tasiast gold deposit. The Tijirit mineralized zones are trending to the NNE and are rather sub-parallel to the Tasiast north-trending deposit. The style of gold mineralization varies on the Tijirit project; however, two major types have been identified as unique: Eleonore-type mineralization and BIFs type.
On Tijirit, gold mineralization is related to deformation zones affecting the iron formations, various metasedimentary sequences and intermediate and mafic metavolcanic and meta-igneous rocks. Gold is locally visible, mostly as native medium to small grain located in quartz ± carbonate veins and silicified zones within highly schistozed metabasites and locally associated with sulphides and metasediments or with quartz veins and altered zones near meta-igneous rocks.
The Tijirit mineralization can be classified according to the following:
Sophie I, II - gold is related to quartz-carbonate-sulfide veining located in altered, sheared and folded zone within or near contacts between BIF (iron formation), metabasic and metasedimentary sequences.
Sophie III - gold is located in the north limb of a regional fold in NE-trending sheared contact between metavolcanics and metasediments.
Lily - gold appear as fine grains located in widespread quartz-carbonate-sulfide veinlets associated to various zones, showing disseminated pyrrhotite and pyrite, alteration and shear and transposition deformation mostly in metasediments, meta-igneous and metabasic NE-trending sequences.
Eleonore1 - medium to fine grained gold is seen in various size quartz-carbonate-sulfide veining associated with shear and alteration zones within or in contact zones between meta-igneous, metasediments and metabasic rocks.
Salma - gold is related to late-tectonic quartz veins locally showing sulfides and host-rock alteration. Gold is concentrated in quartz veins trending north, dipping west and located either at the contact between the metabasite sequences and the granite, 250 or 600 m east of the contact in identical veins or within the metabasite sequence, 1 km west of the contact with similar type of quartz veins. The Salma structure can be followed over a 10-km strike.
At present, different types of gold mineralisation have been identified at the Tijirit project. It appears that gold mineralization is not always related to the iron formations but as in Tasiast the presence of iron-rich rocks in the vicinity or lithological density contrasts could have play a structural and/or mechanical role in the precipitation of gold. It is carried through fluid vector circulation resulting in potassic alteration and quartz veins or stockworks or pervasive silica and/or carbonate and sulphide-rich precipitation.
Summary:
The mining method selected for the Project is a conventional truck and shovel, drill and blast quarry operation. The mineralised material and waste rock will be mined at 5 m high benches, drilled, blasted and loaded into rigid quarry haul trucks with hydraulic excavators.
The mine plan was established annually for the first four (4) years of production at a rate of 2,976 t/d, followed by a four (4) year period at 4,500 t/d. The annual production target will be 1,086,240 tonnes for Phase 1 and 1,642,500 tonnes for Phase 2. (with 138,805 tonnes in Year 8).
Seventeen (17) pits were designed for the Project resulting in just over 7 years of production between Phase 1 and Phase 2.
Flow Sheet:
Crusher / Mill Type | Model | Size | Power | Quantity |
Jaw crusher
|
|
|
132 kW
|
1
|
Cone crusher
|
|
|
185 kW
|
1
|
SAG mill
|
|
|
3300 kW
|
1
|
Ball mill
|
|
|
3300 kW
|
1
|
Summary:
Crushing Circuit
ROM mineralised rock is delivered by 55 tonne haul-type trucks to the crusher feed stockpile area. The rock is delivered directly into the crushing circuit feed hopper or stored in one of the two stockpiles (divided into high grade and low grade material). ROM rock stored in the stockpiles can be blended if necessary to stabilize the plant feed grade when multiple pits are being mined simultaneously. Each stockpile has a live capacity of 6,000 tonnes.
The high and low grade stockpiles are located within the same area as the crushing circuit equipment. The stockpiles are reclaimed by front-end-loader and fed into the crushing circuit feed hopper when the haul trucks are not directly dumping into this hopper. ROM dumped into the crushing circuit feed hopper is fed to a jaw crusher. A variable speed apron feeder transfers the crushed mineralised rock from the crusher onto the crushed rock conveyor. The speed of the apron feeder is used to control the crushing circuit throughput.
The Phase 1 grinding circuit requires finer feed material as it consists of a single grinding stage. A 132 kW jaw crusher has been selected for this flowsheet.
Crushed material at the crusher discharge is conveyed to the Coarse Mineralised Rock Stockpile via the crushed rock conveyor. The stockpile has a live capacity of 4,500 tonnes, which will provide up to a day of feed material to the grinding circuit during Phase 2, and as much as a day and half during Phase 1. The stockpile ensures the processing plant operates independently of the mining and crushing activities, providing constant feed to the grinding circuit.
Grinding Circuit
Crushed Mineralised Rock stored in the Crushed Rock Stockpile is reclaimed by two variable speed apron feeders (one operating and one standby). The speed of the apron feeders will be used to control the processing plant throughput. From the apron feeders, the crushed mineralised rock is fed to the SemiAutogenous (SAG) grinding mill by a belt conveyor. The coarse mineralised rock is ground as slurry in the SAG mill with the addition of process water. The SAG mill will operate in closed circuit with a cluster of hydrocyclones. A re-circulating load of 400 % was selected for equipment sizing. The targeted cyclone overflow size has an 80% passing size of 105 microns. The selected SAG mill has an installed power of 3300 kW and was selected to operate in both the Phase 1 and Phase 2 circuits.
SAG mill discharge passes over a trommel screen to remove oversize material (pebbles), which are recycled internally in the SAG mill with a water jet system. Phase 1 operation does not include the use of a pebble crusher. Trommel screen undersize flows by gravity to a pump box from where it is pumped by one of two pumps (one operating and one standby) to the hydrocyclone cluster.
Phase 2 of operations will see an increase in the average grinding circuit throughput, from 2,976 t/d to 4,500 t/d, and a reduction in the target of the 80% passing size of the grinding circuit from 105 microns to 75 microns. In order to achieve this, several changes will be made to the grinding and gravity circuits.
Several modifications will be made to the grinding circuit to change it from a single stage grinding circuit to a two-stage grinding circuit. The following equipment will be added to the circuit:
• A pebble cone crusher;
• A ball mil;
The SAG mill will be operated in an open circuit-configuration. Crushed mineralised rock will be fed to the SAG mill along with water. Ground rock from the SAG mill trommel undersize will gravitate to the hydrocyclone feed pump box.
A pebble crusher will be added to the SAG mill circuit in Phase 2 to crush pebbles generated from the increased throughput and reduced grinding action in the SAG mill. SAG mill trommel oversize is conveyed to the cone crusher and returned to the SAG mill, also via a belt conveyor. The selected cone crusher will have an installed power of 185 kW.
The new hydrocyclone will operate in closed circuit with a ball mill. The selected ball mill will have an installed power of 3,300 kW. This size has been selected in part to meet the throughput and grind size requirements, but also to maximize the interchangeability of parts between the SAG and ball mills. The ball mill trommel undersize is directed to the hydrocyclone feed pump box, while the overflow is simply discarded in bins.
Processing
- Gravity separation
- Centrifugal concentrator
- Carbon re-activation kiln
- Hydrochloric acid (reagent)
- Intensive Cyanidation Reactor (ICR)
- Dewatering
- Filter press plant
- Agitated tank (VAT) leaching
- Concentrate leach
- Carbon in leach (CIL)
- Elution
- AARL elution
- Carbon adsorption-desorption-recovery (ADR)
- Solvent Extraction & Electrowinning
- Cyanide (reagent)
- Rotary kiln & Electric furnace
Flow Sheet:
Summary:
The process plant was developed for two distinct phases of production. In the first phase of production, the plant was designed for an average daily capacity of 2,976 tonnes of run of mine (ROM) processed from the higher-grade deposits, mostly located in the Eleonore mining zone. After approximately four years of operation, the plant will undergo an expansion in order to process 4,500 average tonnes per day of ROM processed from the lower-grade deposits, located in the Lily and Sophie mining zones. For both phases, the process plant consists of traditional gravity and Carbon- In-Leach (CIL) circuits, followed by electrowinning to produce doré bars.
The Phase 1 average plant design feed grade is of 3.33 g/t Au, while in Phase 2, the average plant feed grade decreases to 1.07 g/t Au. Yearly gold production will vary between 50,000 oz. and 123,000 oz. of doré bars depending on the plant feed rate and grade.
Gravity Circuit
The hydrocylcone overflow is the fi ........

Recoveries & Grades:
Commodity | Parameter | Avg. LOM |
Gold
|
Head Grade, g/t
| 2.08 |
Projected Production:
Commodity | Units | Avg. Annual | LOM |
Gold
|
oz
| 104,500 | 580,901 |
All production numbers are expressed as metal in doré.
Operational Metrics:
Metrics | |
Stripping / waste ratio
| 12.2 * |
Waste tonnes, LOM
| 111,915 kt * |
Ore tonnes mined, LOM
| 9,140 kt * |
Total tonnes mined, LOM
| 121,055 kt * |
Daily processing capacity
| 2,976 t * |
Tonnes processed, LOM
| 9,140 kt * |
Annual processing capacity
| 1,100 kt * |
Annual ore mining rate
| 1,018 kt * |
* According to 2018 study.
Reserves at May 12, 2021:
The mineral resources are presented at a 0.4 g/t Au cut-off grade in pits and 1.7 g/t Au cut-off grade under the pits, except for Eleonore, where a global cut-off of 1.5 g/t Au was applied
Category | Tonnage | Commodity | Grade | Contained Metal |
Measured
|
668,000 t
|
Gold
|
2.53 g/t
|
54,500 oz
|
Indicated
|
3,485,000 t
|
Gold
|
2.13 g/t
|
238,100 oz
|
Measured & Indicated
|
4,154,000 t
|
Gold
|
2.19 g/t
|
292,600 oz
|
Inferred
|
10,160,000 t
|
Gold
|
1.63 g/t
|
533,200 oz
|
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