Overview
Stage | Permitting |
Mine Type | Open Pit |
Commodities |
|
Mining Method |
|
Processing |
- Gravity separation
- Flotation
- Agitated tank (VAT) leaching
- Concentrate leach
- Carbon in leach (CIL)
- Carbon adsorption-desorption-recovery (ADR)
- Elution
- Solvent Extraction & Electrowinning
- Cyanide (reagent)
|
Mine Life | 22 years (as of Jan 1, 2019) |
Latest News | Gold X Mining – Fast Track to Mining License May 27, 2020 |
Source:
p. 7
The Toroparu Project is the Company’s primary resource properties, and is held and operated through ETK, the Company’s wholly-owned subsidiary.
Deposit Type
- Breccia pipe / Stockwork
- Intrusion related
Summary:
The Toroparu Deposit occurs on the northeast border of a tonalite pluton. Mineralization is hosted by Paleo-Proterozoic greenschist metamorphic volcano-sedimentary sequence in contact with a tonalitic to quartz-dioritic intrusive. The deposit forms a west-northwestern oriented mineralized corridor, where the Au and Cu mineralization appear to be controlled by a moderately developed, probably dilational type of brittle fracture/veinlet stockwork.
Au mineralization grades in saprolite and in fresh rock are similar with no apparent depletion or concentration of Au values with respect to fresh rock, with the noted exception of the concentrated Au in the thin overlying alluvial cover. Therefore, Au grades are treated similarly in saprolite and fresh rock for grade estimation in the block modeling. A Au grade shell was created using Leapfrog® software and anisotropy places drawn through the higher-grades as structural control to an 0.2 g.t grade shell. That grade shell was modified by the removal of barren zones internal to the 0.2 grade shell, and modification in plan and section to better fit the Au assay data. Copper mineralization was modeled as a 0.04% Cu grade shell with similar structural controls.
The existing exploration results suggest that the Toroparu Deposit is an Au-Cu-bearing mineralized system hosted by a sequence of metamorphosed pyroclastics and minor volcanic flows and sediments adjacent to an altered granodiorite pluton. The mineralization consists of disseminated sulfides in a veinlet and fine fracture/stockwork, which could be shear-zone related.
The Toroparu Deposit shows a better resemblance to the Archean-aged Boddington deposit. Both deposits are hosted by greenschist metamorphosed volcanics, sub-volcanics, and intrusives, and show a similar mineralization style. The Boddington deposit in Australia is interpreted as a structurally controlled, low-sulfidation, intrusion-related Au-Cu deposit formed by two overprinting magmatic-hydrothermal events. The bulk of the mineralization and associated alteration are genetically related to a K-rich post tectonic magmatic suite of intrusions (McCuaig, et. al., 2001).
The Deposit Type, as a whole for the Property, can be described as intrusive-related Au and Au-Cu mineralization. The individual variance between deposits is seen in the presence or absence of sufficient Cu to be of economic interest, the host rock as intrusive or meta-volcanic rocks, and the structural setting being related to shear zones or major structural intersections or deflections.
Summary:
The mining operations start in year -1 at a capacity close to 10 Mt/y and this is ramped-up to 20 Mt/y in year 3. This production rate is kept at this level until year 10, when the mining capacity is increased to 32 Mt/y in preparation of the installation of the flotation circuit in year 11. The mining capacity is ramped-up again in year 14 when it is increased to a maximum capacity of 42 Mt/y.
The Project’s mine production is supported by three open pits, including the Main pit, the Southeast pit and the Sona-Hill pit. Production starts in year -1 at the Main and Sona-Hill pits and eventually includes the Southeast pit in year 2. A combination of these three pits compose the mine production until year 9, when both Sona-Hill and Southeast pits are depleted. The Main pit supports the production alone from year 10 to 23.
Mining will consist of a conventional open pit operation including drilling and blasting, loading and hauling. It is contemplated that a hydraulic excavator and haul truck mining fleet will be utilized, along with supporting auxiliary mining equipment (motor graders, water trucks, etc.).
The Toroparu Main Pit is planned to be developed first, with the process facility to be constructed adjacent to this pit. This will minimize the economic material haulage requirements during the early years of the Project.
The South-East Pit is started in Year 2 (2nd year of processing production). The Sona Hill Pit will also be mined at the same time as the Toroparu Main Pit. The Project plans to use proven technology, with no requirement for untried or untested technology.
The overall objective of the pit slope design was to determine the steepest practical slope angles to maximize extraction of the mineral resources. The pit slope design was based on the available geotechnical database, geological/structural models and corresponding stability analysis results. This work led to the development of pit slope design parameters for benches, inter-ramp slopes, and overall slopes in each of the pit design sectors of the proposed open pits.
A bench face angle of 65° is expected to be appropriate for the Saprolite slopes provided that adequate catch benches are emplaced. A 10 m high single bench configuration with a minimum bench width of 8 m is recommended for the Saprolite slopes, assuming moderately sized mining equipment being used for pit development.
In Fresh Bedrock, a slightly flatter bench face angle of 65° is deemed to be appropriate for the MNorth, SE-Northeast, and SE-Southeast Sectors due to potential planar daylighting and/or minor wedge/toppling. A bench face angle of 70° is achievable for the M-East, and SE-Northwest, SHNortheast, and SH- Southeast Sectors despite the minor potential for planar/wedge sliding and potential toppling caused by inferred faults. A steeper bench face angle of 75° can be applied for the M-South, M-West, SH-Southwest and SH-Northwest Sectors as foreseeable kinematic control is absent. Given the nature of competent rock mass, 20 m high double benching configurations can be considered for the pit walls developed within the Fresh Bedrock. The bench width is recommended to be between 9.5 and 10 m to catch possible raveling and rock fall debris.
The inter-ramp slope angles are typically determined by the bench geometry. A shallow inter- ramp angle of 38° is recommended in the Saprolite slopes. The bedrock slopes in the M-North, SENortheast, and SH- Southeast Sectors are limited to an inter-ramp angle of 47° due to the presence of adverse planar features. A 50° inter-ramp angle is recommended for the M-East and SE-Northwest Sectors where the potential for minor adverse structural features are identified. A slightly flatter 49° inter-ramp angle is recommended for the SH-Northeast and SH-Southeast Sectors where a low angle shear zone/foliation feature is present but is not expected to have major adverse impact to the pit walls. A steeper inter-ramp slope angle of 53° can be applied for the slopes with fewer kinematic controls, including the M-South, M-West, SH-Southwest, and SH-Northwest Sectors.
A 20 m wide catch bench should be placed immediately below the saprolite/bedrock contact to intersect the surface runoff and seepage inflow and to provide additional containment capacity for potential saprolite raveling during wet seasons. It is also recommended that the maximum height of inter-ramp slope in the Fresh Bedrock domain be limited to 200 m in the Main Pit. The overall slope angles are expected to be 5° to 8° flatter than the inter-ramp slopes in bedrock after the flatter Saprolite slopes, wider catch bench, and spiral haulage ramps are incorporated.
Processing
- Gravity separation
- Flotation
- Agitated tank (VAT) leaching
- Concentrate leach
- Carbon in leach (CIL)
- Carbon adsorption-desorption-recovery (ADR)
- Elution
- Solvent Extraction & Electrowinning
- Cyanide (reagent)
Flow Sheet:
Summary:
The processing plant will be constructed in two phases. The first phase consists of the initial 10 years of the Project where the plant will receive LCO and saprolitic material to recover Au. During the second phase, the plant will be expanded with the addition of a Cu flotation circuit and the associated equipment to produce a Cu concentrate. The overall plant capacity will double in size to 23,000 t/d with the addition of the flotation circuit.
Phase 1 processes 11,500 t/d of LCO and saprolite material through crushing and grinding, Carbonin-Leach (CIL) circuit and ADR to produce Au doré. This phase continues through the LoM.
In Phase 2, ACO will be of processed at 11,500 t/d of ACO through flotation with cyanide leaching of the cleaner scavenger flotation tailings via a CIL circuit. Based on metallurgical testwork recovery by flotation, a Cu concentrate with grade of approximately 21% Cu is expected to be produced. Gravity concentration with intense cyanidatio ........

Recoveries & Grades:
Commodity | Parameter | Avg. LOM |
Gold
|
Head Grade, g/t
| 1.01 |
Copper
|
Concentrate Grade, %
| ......  |
Copper
|
Head Grade, %
| 0.1 |
Silver
|
Head Grade, g/t
| 1.19 |
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Reserves at June 1, 2019:
Category | Tonnage | Commodity | Grade | Contained Metal |
Measured & Indicated
|
147,871,624 t
|
Gold
|
1.02 g/t
|
4,862,857 oz
|
Measured & Indicated
|
147,871,624 t
|
Copper
|
0.1 %
|
148,722 t
|
Measured & Indicated
|
147,871,624 t
|
Silver
|
1.22 g/t
|
5,809,743 oz
|
Inferred
|
8,482,296 t
|
Gold
|
0.85 g/t
|
232,143 oz
|
Inferred
|
8,482,296 t
|
Copper
|
0.05 %
|
4,315 t
|
Inferred
|
8,482,296 t
|
Silver
|
0.59 g/t
|
160,257 oz
|
Mine Management:
Job Title | Name | Ref. Date |
.......................
|
.......................
|
Mar 3, 2020
|
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Corporate Filings & Presentations:
Document | Year |
...................................
|
2019
|
...................................
|
2019
|
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News:
Aerial view:
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