Introduction
Adamus Resources Limited (Nzema Gold Mine) is located approximately 300km west-southwest by road from the Capital City Accra, and 80km west by road from the port of Takoradi.
Adamus Resources Limited is the first mine to be owned by Nguvu Mining. The mine was acquired from Endeavour Mining in 2017. Nguvu Mining has 90% economic interest in the mine, with the Government of Ghana holding the remaining 10%.
Mining activities is by owner mining
The mine commenced initial mining operations in November 2010 and commercial production in April 2011. The mine employs conventional open pit mining method. Mining activities is by owner mining.
The mined ore is processed by Carbon-in Leach (CIL) technology. The processing plant is designed to treat oxide, transition, and primary ores. The design throughput treatment rate depends on the hardness of the ore with 2.1 Mtpa of softer oxide ore and 1.6 Mtpa of the harder transition and fresh ore. The mine has approximately a workforce of 1,228; made up of 1% expat and 99% Ghanaians, of which about 59% are from the local communities.
The major gold deposits in Ghana are hosted by Palaeoproterozoic rocks of the West African Craton, which includes the Birimian Supergroup, a series of meta-volcanic and meta-sedimentary rocks, the Tarkwaian Group, comprising fluvial meta-sedimentary rocks, and various gabbroic to granitic intrusive, as shown in figure 2 above.
Gold mineralization within the Birimian Supergroup is associated with mesothermal quartz veins and structurally controlled, while both mesothermal shear-hosted and palaeoplacer gold deposits occur in the Tarkwaian Group. The Project area is underlain by Birimian Supergroup rocks with minor granitic intrusions, bounded by large granitoid bodies to the west and east, and poorly defined areas of Tarkwaian Group in the east.
The major gold deposits in Ghana are hosted by Palaeoproterozoic rocks
Metamorphic grade of the Birimian rocks is greenschist facies, with local amphibolite facies aureoles around granitoid plutons. Recent work in the southern Ashanti region suggests that the greenschist facies is widely retrograde after amphibolite facies conditions. Both belt and basin packages are highly deformed with widespread isoclinal folding and regional bedding-parallel cleavage attributed to regional northwest–southeast compression during the peak of the Eburnian Orogeny c. 2100 Ma. Regional northeast striking shear zones parallel to the belt margins are also assumed to have developed during peak Eburnian and appear to be fundamentally important in the development of the Birimian gold deposits for which Ghana is well known such as Ashanti, Prestea-Bogosu, Konongo, and Bibiani. ARL’s Nzema Gold Project covers the south-western margin of the famous Ashanti Belt.
The Nzema Gold Mine is located at the southern end on one of the five parallel and evenly spaced belts of folded Birirmian metalavas, known as the Ashanti belt. The deposits have been identified into three main groups, namely, The Salman Trend, the Anwia (Adamus) deposit, and the Satellite deposits.
Discovery Target of ≥ 350K oz, to be achieved from 2021 - 2023
The Nzema Gold Project is a Land Package of about 369.95km², located at Southwest Ghana. The Land Package is made up of 4- Mining Leases and 8-Prospecting Licenses with 2 JV Permits.
A vast exploration potential exists on the Mining Leases and the surrounding Prospecting Permits, which are currently being explored for economic gold deposits discoveries for LOM extension.
A total resource of 973K oz @ 1.80g/t Au of untapped refractory Salman ‘sulphide’ ore exist. Metallurgical studies to find appropriate treatment method for the ‘sulphide’ ore is underway.
NZEMA PROJECT- SUMMARY GEOLOGY & MINERALIZATION
The Nzema Project area straddles the Ashanti belt-Kumasi Basin margin. It is currently the only large-scale operating Mine south of the Prestea-Iduapriem Mines. The geology of the project area is dominated by alternating thick bands of greywacke & phyllite to the west of the Ashanti fault. Some of the greywacke-phyllite contacts are sheared with gold mineralization often localized in structures associated with these shears/faults. Further west into the basin, the phyllites-greywacke units have been multiply folded with gold mineralization often hosted in fold related structures. Typical fold related gold deposits in the Nzema land package include the Adamus deposit- hosted at a fold limb and the Nfutu deposit- hosted at a fold nose.
The dominant rock types to the east of the Ashanti Fault are meta-volcanics, volcaniclastics & belt sediments. The main structures known to occur at the east of the Nzema Project area are the NNE trending Avrebo shear, which hosts about 40K oz Indicated resource and extensive volcanics-granitoid margins with some untested Geochem anomalies of interest. Several granitoid bodies of various shapes and sizes have intruded both the basin sediments and the volcanics/volcaniclastics units. The intrusive-sediments/volcanics contact areas are part of the potential areas to receive exploration attention.
DEFINED EXPLORATION TARGETS OVER GEOLOGY
The current Nzema Project Pipeline of Exploration targets were developed from integration of interpreting existing Geochem, drilling, Geophysical & Geological data.
Target Generation work via continuing data review, field/pit mapping, rock & soil sampling & Ground Mag survey are being done to define drilling targets for deposits discoveries and LOM extension.
Drill testing of some targets commenced in Jan 2022. Successful targets would be advanced to resource definition stage. MRE to be delivered by end of Qtr-3 2022 for mine planning.
The objective is to progressively produce 350K oz by end of 2023 and replace the depleted reserves at a discovery cost below $20/oz.
THE NZEMA EXPLORATION STRATEGY FOR LOM EXTENSION
1. Development of Existing Assets (Salman-Nfutu-Adamus Deposits & Surroundings) for Incremental Ounces
Salman Trend Remnant ‘Oxide’ & Refractory Ores
- 2021 drilling done for ‘oxide’ ore along the Salman trend focused on targets in the dilatant zone. MRE is expected by end of Qtr-2 2022.
- Salman Deeps- test drilling for the extensions of the ‘sulphide’ ore depth was completed in Jan 2022. The outcome of the drilling confirmed extensions of the ore shoots at approximately 100m below the current resource. Infill drilling for strike and up dip extensions of ore shoots is planned.
Nfutu Deposit (Incremental Ounces Conversion)
- Initial phase of drilling done in 2021 confirmed down plunge extension of med & high-grade ore shoot to the SE. Resource of 327K tons @ 1.47g/t Au is defined.
Adamus Pit (Incremental Ounces Conversion)
- Deep drilling planned to test for potential underground extensions of gold mineralization.
2. Development of Early-Stage Prospective Targets
- Focus on untested exploration targets within5-10km radius from the Processing Plant that have potential to yield economic MRE by Qtr-3 2022.
- These priority targets include Gama, Mamposo, Bernard West and Boanome East extension, Nfutu West, etc.
3. Build Strong Social License for Smooth Operation
- Provide employment & other job opportunities for the locals
- Comply with Environmental & Safety requirements in the catchment areas.
- Provide social support to the communities directly impacted by ARL’s Mining Operations.
Salman Trend - ‘Sulphide’ project, Potential for Resource Upgrade.
- Potential for resource upgrade of the unexploited 973K oz ‘sulphide’ resource at depth and along strike exist
- Existing drilling has probed the mineralization to a vertical depth of around 100m. The ongoing 2021 drilling campaign at the dilatant zone seek to confirm the extensions of the ore shoots to further 100-150m below the current resource. Assays of one initial DD hole returned 8m@3.35g/t Au.
Adamus (Anwia) Deposit- Potential for Resource Addition
- The last 106Kt @ 2.07g/t (7Koz) reserve yet to be depleted.
- Mineralization controlled by stacked sub-horizontal & steeply NW dipping structures
- There is high potential for repeat of the mineralized system below pit bottom.
- Deep drilling planned for execution in 2023.
- Quick generation of additional ounces to extend LOM
1987
1987
Akango Area of Salman deposit Held
Ghanorcan Resources holds Akango area of the Salman deposit.
1995
1995
Temco held AKANGOPL Covering old Akango Mine Salman area
1995
Semfo explored Teleku Bokazo and EBI PL
1995
Nkroful Mining JV with Samax (Bokrobo Aliva area)
1995
BHP JV and purchases in the area confirmed Salman trend
1999
1999
Salman acquired from BHP
AGR acquires Salman from BHP.
1999