Overview
Stage | Preliminary Economic Assessment |
Mine Type | Open Pit |
Commodities |
|
Mining Method |
|
Mine Life | 10.3 years (as of Jan 1, 2021) |
For the Adumbi deposit PEA, two financial model options were examined: the diesel-only option of generating power for essential processing plant equipment and infrastructure; and the HEP hybrid option, which is a hybrid system consisting of HEP supplemented by diesel and solar PV power generation with a Battery energy storage system (BESS).
It was assumed that the capital cost for the HEP option would be funded by Loncor. However, Loncor is already in discussion with potential power suppliers with experience in the DRC to project finance and build a HEP facility near the Adumbi deposit area and then have an offtake agreement with Loncor to supply power for the operation. Any hydroelectric power scheme could also have the potential to obtain carbon credits. |
Source:
p. 34
Company | Interest | Ownership |
Government of the Democratic Republic of the Congo
|
10 %
|
Indirect
|
Loncor Gold Inc.
|
84.68 %
|
Indirect
|
Loncor holds 84.68 % interest in the Imbo Project through its subsidiary Adumbi Mining S.A., with the minority shareholders holding 15.32 % (including the 10 % free-carried interest held by the Government of the DRC).
Contractors
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Deposit Type
- Banded iron formation
- Orogenic
- Mesothermal
Summary:
Gold deposits within the Imbo Project are associated with the globally important Neo-Archean orogenic gold deposits. Gold mineralisation is associated with the epigenetic mesothermal style of mineralisation. This style of mineralisation is typical of gold deposits in Neo-Archean greenstone terranes and is generally associated with regionally metamorphosed rocks that have experienced a long history of thermal and deformational events. These deposits are invariably structurally controlled.
The Adumbi gold deposit is found within the Ngayu Archean greenstone belt, one of a number of Archean-aged, granite-greenstone belts that extend from northern Tanzania into northeastern DRC and then into the Central African Republic. The greenstone belt terrain in northeastern DRC has a number of major gold belts including Moto (Kibali), Kilo, Mambasa, Ngayu and Isiro.
The Adumbi deposit displays five distinct geological domains with the BIF unit attaining a thickness of up to 130 m in the central part. There is a higher-grade zone of gold mineralisation termed the “replaced rock zone” (RP zone) associated with alteration and structural deformation that has completely destroyed the primary host lithological fabric. The RP zone occurs in the lower part of the Upper BIF package and in the Lower BIF package, and transgresses the Carbonaceous Marker, located between the Upper and Lower BIF packages, both along strike and down dip. The geological interpretation from the Lonc ........
Summary:
Over the life of mine (LOM) of Adumbi, a total of 49.77 Mt grading 2.17 g/t Au is expected to be mined from the open pit and delivered to the processing plant.
The scheduling process consists of developing a mine plan that is economically optimal using the inventory included in the practical pit designs and pit shell. The production schedule was based on a methodology of block selections from the block model inside the designed pits.
The mining production schedule sequence is planned to mine the Cut 1 and Cut 2 pit designs from the beginning of Year 1 to get rapid access to the ore and manage the strip ratio. Mining of the Cut 3 pit shell starts from the beginning of Year 2. The Adumbi deposit is planned to be to provide a throughput of 5.0 Mt/a of ore to the processing plant. Adumbi has an average stripping ratio of 11:1.
A conventional open-pit shovel-and-truck method will be used for the mining of sufficient ore to supply a 5.0 Mt/a of oxide, transition and fresh ore throughput. The mining functions of the operation will be carried out by a mining contractor.
The practical pit design incorporates the ramps together with the appropriate inter-ramp slope angles.
The open-pit design criteria were as follows:
• A nominal bench height of 8 m;
• The inclusion of the ramping systems, resulting in the recommended overall slope angles of approximately 40° to 45° being achieved;
• Haul road widths of 25 m, includi ........
Source:
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Flow Sheet:
Summary:
- subscription is required.
Projected Production:
Commodity | Product | Units | Avg. Annual | LOM |
Gold
|
Payable metal
|
koz
| | 3,119 |
Gold
|
Metal in doré
|
koz
| 303 | 3,121 |
Operational Metrics:
Metrics | |
Annual mining capacity
| ...... |
Annual ore mining rate
| ...... |
Plant annual capacity
| ...... |
Stripping / waste ratio
| ...... |
Waste tonnes, LOM
| ...... |
Ore tonnes mined, LOM
| ...... |
Total tonnes mined, LOM
| ...... |
Tonnes processed, LOM
| ...... |
* According to 2021 study.
Reserves at November 17, 2021:
Mineral resources were estimated at a block cut-off grade of 0.52 g/t Au for oxide, 0.57 g/t Au for transition and 0.63 g/t Au for fresh material constrained by a Whittle pit.
Category | OreType | Tonnage | Commodity | Grade | Contained Metal |
Indicated
|
Sulphide
|
21,614,000 t
|
Gold
|
2.02 g/t
|
1,400,000 oz
|
Indicated
|
Transitional
|
3,401,000 t
|
Gold
|
2.51 g/t
|
274,000 oz
|
Indicated
|
Oxide
|
3,169,000 t
|
Gold
|
2.05 g/t
|
208,000 oz
|
Indicated
|
Total
|
28,185,000 t
|
Gold
|
2.08 g/t
|
1,883,000 oz
|
Inferred
|
Sulphide
|
20,089,000 t
|
Gold
|
2.64 g/t
|
1,703,000 oz
|
Inferred
|
Transitional
|
280,000 t
|
Gold
|
2.74 g/t
|
24,000 oz
|
Inferred
|
Oxide
|
458,000 t
|
Gold
|
3.39 g/t
|
49,000 oz
|
Inferred
|
Total
|
20,828,000 t
|
Gold
|
2.65 g/t
|
1,777,000 oz
|
Corporate Filings & Presentations:
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