The Kalongwe project is a high-grade copper-cobalt mine located in Lualaba Province of Democratic Republic of Congo (DRC).
Kalongwe Mining, a joint venture company, is developing the project in two stages. Nzuri Copper holds 85% stake in Kalongwe Mining, while La Generale Industrielle et Commerciale au Congo (GICC) and the Democratic Republic of Congo Government hold 10% and 5% respectively.
Feasibility study of the first phase of the project was completed in October 2017 and updated in April 2018. A full SX-EW DFS for the second phase is planned to be undertaken.
The project is expected to produce 18,657 tons per annum (tpa) of copper and 1,370tpa of cobalt in concentrates on an average, through its anticipated mine life of eight years.
Kalongwe copper-cobalt project geology and mineralization
The Kalongwe copper-cobalt project is located towards the western portion of the Central African Copper Belt and hosts deeply weathered, sediment-hosted copper mineralization. It is classified as a high-grade oxide near-surface copper-cobalt resource.
Fragments of mine series rock have been found at the southwest-trending anticline structure in the project area. Kalongwe fragment stretches over a length of 450m and hosts the significant supergene mineralization at surface.
Most of the sulphide mineralization is identified in ex-dolomitic siltstones and stromatolitic dolostone and siltstones host rocks.
Primary mineralization is deposited in the ex-dolomitic siltstones, stromatolitic dolostone, and siltstones host rocks. The deformed host rocks of the project form fragments and are identified in the core of anticlines within the Lufilian Fold Belt.
Secondary mineralization is fracture controlled and hosted in part stratabound. Malachite is the principal copper oxide mineral found at the deposit, which also contains minimal amounts of azurite and chrysocolla along with cobalt (as heterogenite).
Copper reserves at Kalongwe project
As of April 2018, the proven and probable ore reserves at Kalongwe were estimated to be 7.99 million tons (Mt) grading 2.94% Cu and 0.34% Co. The mine is estimated to contain 234.9Mt of copper and 27,102t of cobalt.
Mining ore processing at Kalongwe copper-cobalt project
Conventional open-pit mining method with drilling and blasting followed by truck and shovel will be applied at the Kalongwe. The major mining fleet will comprise 90t excavators, 40t articulated dump trucks, and a top hammer drill rig.
The first phase of project development will comprise an open-pit mine and on-site 1Mtpa dense media separation (DMS) processing plant featuring two single-stage modules. The second phase is expected to comprise a full-scale SXEW plant and cobalt circuit to process DMS-generated rejects and cobalt-only ore.
Ore will be initially crushed in the primary crusher to produce a coarse product, which will be forwarded to the scrubber and DMS circuit. It will then be passed through scrubber and secondary crusher with cone crusher in closed circuit to produce feed for the DMS circuit.
Undersize material from the scrubber wet screen will be de-slimed to produce a mineralized sands product, which will be further treated using a spirals circuit to produce a spirals concentrate product.
At the DMS, two single-stage modules will process the ore to produce a rejects stream and concentrate product. The final DMS and spiral concentrate product will be transported to the bagging station and packed in 1.5t bags.
Tembo Capital (a partnership of Tembo Capital Mining Fund and Ndovu Capital), a major shareholder of Nzuri, has provided a loan facility of A$3m ($2.1m) under a binding term sheet, in February 2019.
Tembo also provided a convertible loan of $2.93m to Nzuri in May 2018 for the project development.
Huayou International Mining (Hong Kong), a fully-owned subsidiary of Zhejiang Huayou Cobalt (Huayou Cobalt), invested A$10m ($7.6m) in Nzuri and acquired 14.76% stake in December 2017. Nzuri proposed to use the proceeds raised for the development and optimization of the Kalongwe project, along with undertaking exploration activities.
Infrastructure facilities at the Kalongwe copper-cobalt project
The project will use the existing unsealed roads built by Ivanhoe Mines to access their Kamoa and Kakula deposits and from there a new 28km access road.
Power supply will be provided by an on-site hybrid power station, comprising seven 400kW diesel generators. A 600kWp photovoltaic array will also be constructed to support the onsite power station and to minimize fuel.
Water required for the processing facilities will be collected from a dewatering borefield located around the open-pit and from a water storage dam with water collected from the Kalongwe River.
Process water will be recycled within the main process plant, while potable water will be generated by a water treatment plant located at the camp.
Workers will be temporarily accommodated at the 170-person construction camp, while a 250-person permanent accommodation camp is proposed to be constructed.
Lycopodium Minerals was engaged as the principal contractor for the FS and is supported by consultants such as Knight Piesold, Orelogy, CSA Global, African Drilling, MSA, and Miller Metallurgical Services.
Lycopodium was also engaged for preparing the front-end engineering and design (FEED) for phase one of the DMS plant and phase two economic assessment study.
Knight Piesold was engaged for designing the tailings storage facility of the Kalongwe copper-cobalt project, while ECG Engineering prepared the power supply study.