Source:
p. 42
Summary of Property Ownership:
- CMMA (subsidiary) - 98.45 %
- Promotora Avino, S.A. de C.V. (subsidiary) - 1.22 %
- Estate of Ysita (non-controlling interest) - 0.33 %
Summary:
The oxide tailings deposit comprises historic recovery plant residue material that was wasted from processing plants during the earlier period of open pit mining of the Avino Vein. The oxide tailings are partially covered by younger unconsolidated sulphide tailings on the northwest side.
The Avino tailings dam is located approximately 500 m west southwest of the main shaft to the old underground workings and 2.5 km southwest of the San Gonzalo Vein.
Within the tailings dam, there are three distinct benches:
* lower oxide bench
* middle oxide bench
* upper bench or sulphide bench.
Due to the historical processing sequence, the oxide tailings are primarily derived from weathered and oxidized rocks close to the surface on the Property, whereas the sulphide tailings are predominantly derived from material sourced at depth from the underground workings, below the weathered/leached zone.
In the oxide zone, mineralization is primarily hosted by the minerals argentite, bromargyrite, chalcopyrite, chalcocite, galena, sphalerite, bornite, native silver, gold, and native copper. Other minerals present in mineralized areas, but not hosting the metals of interest, include hematite, chlorite, quartz, barite, pyrite, arsenopyrite and pyrrhotite. Malachite, anglesite and limonite are common in the quartz zones of the weathered parts of the oxide material.
Summary:
The oxide tailings Mineral Resource will be mined/moved using a conventional truck/loader surface mining method. The production cycle consists of loading and trucking.
The production schedule has been developed for the oxide tailings based on a treatment rate of 500 kt/a. This would be equivalent to a throughput rate of 1,370 t/d. This will give an overall Project duration of approximately eight years. This eight-year period includes one year of pre-production and excludes the time required for remediation of the heap after the leaching process has been completed. Only oxide tailings will be considered for treatment, while sulphide materials will be considered waste.
The mining operations include loading and trucking. A 3.85 m3 rated (5.0 yd3) front-end loader will be used to load a 24 t articulated truck that will either deliver the sulphide tailings to the sulphide stockpile or the oxide tailings to the 160 t oxide tailings hopper. Once the hopper is filled, excess tailings will be stockpiled around the hopper to be loaded by the process plant group.
Certain areas of the tailings might contain high amounts of moisture that can lead to equipment getting stuck. To mitigate this challenge, wider, oversized tires with chains will be installed on the front-end loader. Also, the front-end loader bucket will be downsized to 3.06 m3 (4.0 yd3). This will lighten the load on the front tires preventing them from sinking into saturated material. The trucks will not enter the soft zones so there will be no modifications to the trucks.
Processing
- Filter press plant
- Smelting
- Heap leach
- Merrill–Crowe
- Cyanide (reagent)
Flow Sheet:
Summary:
The proposed treatment plant will consist of agglomeration and cyanide heap leaching, followed by a Merrill-Crowe process to recover silver and gold from pregnant solution.
For an oxide tailings treatment rate of 0.5 Mt/a, an equivalent throughput rate of 1,370 t/d or 63.4 t/h is required. This will give an overall Project duration of approximately seven years. This seven year period will exclude the time required for site establishment and remediation of the heap after the leaching process has been completed.
A dribble chute will feed the tailings from the hopper onto a conveyor belt. Cement and lime will be added to the tailings at controlled addition rates. Although some operations add solid dry, flake cyanide to the agglomerator feed material, this option will not be exercised in this case. The cement and lime will be added from their respective bulk storage silos. A 50 t capacity cement storage silo equipped with a dust collection filter and a cement blower ........

Recoveries & Grades:
Commodity | Parameter | Avg. LOM |
Silver
|
Head Grade, g/t
| 87.8 |
Gold
|
Head Grade, g/t
| 0.43 |
Projected Production:
Commodity | Units | Avg. Annual | LOM |
Silver
|
koz
| 882 | 6,173 |
Gold
|
koz
| ......  | ......  |
All production numbers are expressed as metal in doré.
Operational Metrics:
Metrics | |
Daily milling capacity
| 1,370 t * |
Waste tonnes, LOM
| 2,939 kt * |
Ore tonnes mined, LOM
| 3,122 kt * |
Total tonnes mined, LOM
| 6,061 kt * |
Tonnes milled, LOM
| 3,122 kt * |
Annual milling capacity
| 500 kt * |
* According to 2017 study.
Reserves at October 30, 2020:
Cut-off grade is 50 g/t AgEQ for the reported Mineral Resources.
Category | Tonnage | Commodity | Grade | Contained Metal |
Indicated
|
1.12 Mt
|
Silver
|
89 g/t
|
15 koz
|
Indicated
|
1.12 Mt
|
Gold
|
0.42 g/t
|
3.2 M oz
|
Indicated
|
1.12 Mt
|
Silver Equivalent
|
124 g/t
|
4.5 M oz
|
Inferred
|
1.23 Mt
|
Silver
|
85 g/t
|
3.4 M oz
|
Inferred
|
1.23 Mt
|
Gold
|
0.47 g/t
|
19 koz
|
Inferred
|
1.23 Mt
|
Silver Equivalent
|
125 g/t
|
5 M oz
|
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