Overview

Deposit type

• Sediment-hosted

Summary:

The Kinsevere deposit is a sediment hosted copper deposit with low-grade cobalt association.

The deposit is comprised of the R1, R2 and R3 subgroups of the Neoproterozoic Roan Group. Copper mineralisation is generally confined to the Mines (R2) subgroup, however, minor copper-oxide and copper-sulphide development occurs along the R1-R2 contact and the R2-R3 contact.

The deposit is located along a major structural element termed the Kinsevere lineament. Halokenetic and tectonic processes have resulted in the emplacement of discrete lower Roan (R2) stratigraphic blocks onto younger, upper Roan (R3 and above) stratigraphy.

The Kinsevere deposit is comprised of three distinct mineralisation domains: Central, Mashi and Kinsevere Hill. Central and Mashi form a contiguous sequence of mineralised Mine Series correlates that host copper-cobalt oxides and sulphides. Kinsevere Hill represents a structurally isolated occurrence of Mine Series host rocks containing copper-cobalt oxides with minor copper sulphides.

Copper oxide mineralisation is defined as material that has CuAS:CuT ratio between 0.5 to 1. The principal copper oxide mineral is malachite with subordinate chrysocolla, copper clays (Goethite and Mn-WAD), pseudomalachite and rare azurite. Tenorite, native copper and other minor copper oxide phases (Cuintergrows) are also present in minor quantities (~<5% of total Cu oxide mineralogy). The largest proportion of copper oxide mineralisation is hosted in weathered/oxidised carbonates (CMN) as fracture fill, void fill, mineral replacement and coatings. There is a strong preference for copper oxides to develop in CMN lithologies, especially within strongly weathered, brecciated and karstic zones.

Transitional and Mixed Ores (TMO) are copper ores that have an CuAS:CuT ratio between 0.2 and 0.5. Transitional ore zones are classified as zones that contain dominantly transitional copper species such as chalcocite, covellite, cuprite and native copper and are likely to have formed during progressive supergene weathering. Mixed ore zones are defined as containing both sulphide and oxide copper phases present together - particularly malachite, chalcocite and chalcopyrite

Sulphide mineralisation at Kinsevere is defined by all material that has an CuAS:CuT ratio < 0.2. Sulphide mineralisation at Kinsevere has several different modes of development and styles. The three major types are: 1. Replacement of early diagenetic pyrite and evaporites by chalcopyrite and carrolite. 2. Replacement of carbonate minerals by copper and cobalt sulphides. 3. Sulphide bearing veins and vein replacement.

Dimensions
The mineralisation strike length is approximately 1.3 km for the Tshifufia (Central) and Tshifufiamashi (Mashi) deposits while Kinsevere Hill has a 1km strike length. The mineralisation dips sub-vertically. Mineralisation extends to 400 m at depth, and it can be up to 300m in width. The mineralisation outcropped prior to mining.

Mining Methods

• Truck & Shovel / Loader

Summary:

Mining of the Kinsevere deposits is undertaken by the open pit method, which is expected to continue throughout the life of mine.

Kinsevere mine is an open pit operation that is mining and processing oxide copper ore. The operation uses a contract mining fleet of excavators and both rigid body and articulated dump trucks along with a fleet of ancillary equipment.

This mining method is appropriate for the style and size of the mineralisation.

Minimum mining width (bench size) is typically in excess of 45m but is ~35m in some isolated areas during stage development.

All required infrastructure is in place for processing Oxide Copper bearing minerals only. Infrastructure required for the Sulphide plant is outlined in the Kinsevere Expansion Project (KEP) study. Mining rates are planned to stay relatively constant and is within the capacity of the proposed mining contractor capability and capacity.

Comminution

Crushers and Mills

Summary:

Crushing and grinding
- Mineral sizer – this breaks up the rock prior to the semi autogenous grinding (SAG) mill.
- Ore grinding – this uses a single stage SAG mill operating in a closed circuit. This produces a 200 micron feed, which is then directed to the leach tanks. The SAG mill operation is unusual in that sulphuric acid is added to the circuit to start the leach process early in advance of the leach tanks. The leaching process involves the extraction of copper from solid copper oxide using the sulphuric acid solution. Although the acid concentration in the SAG mill circuit is lower than that in the leach tanks, it is very effective because of the high kinetic energy in the SAG mill. The SAG mill has a mild steel shell with an epoxy coating on the inside to prevent acid erosion. The mill is topped up with concentrated acid as necessary.

Processing

• Sulfuric acid (reagent)
• Agitated tank (VAT) leaching
• Counter current decantation (CCD)
• Acid tank leaching
• Solvent Extraction & Electrowinning

Summary:

Kinsevere mines and processes oxide ore. This enables the operation to use the conventional solvent extraction/electrowinning (SXEW) process (Exhibit 3) to produce A grade refined 99.99% copper cathode.

The Kinsevere operation was commissioned in 2007 as a Heavy Media Separation (HMS) operation with a copper concentrate product. The current SXEW plant was completed in 2011 and the HMS plant was closed.

Elements of the current plant and SXEW process include:

Leach tanks – these are atmospheric agitated leach tanks. The residence time in the tanks is six hours. The leached slurry, which contains both copper in solution and un-dissolved copper in solids, passes to the high-grade thickener. High-grade thickener – Overflow from the thickener containing copper in solution, mainly as copper sulphate, passes to a high-grade pinned bed clarifier for further upgrading. Slurry underflow from the thickener, which contains copper not yet dissolved, passes to the counter current decantation (CCD) circuit. High-grade pinned bed clarifier – this removes remaining solids and produces a clarified high-grade pregnant leach solution (PLS), which is the feed for the high-grade circuit of the solvent extraction (SX) process. Underflow from the clarifier is recycled back to the thickener. CCD circuit – Slurry underflow from the thickener is pumped sequentially through five CCD thickeners in series. The slurry underflow liquor is diluted with wash liquor that flows in the opposite direction. The wash liquor leaches out most of the remaining copper in solids and forms the low-grade PLS. After clarification in a low-grade pinned bed clarifier, the clarified lowgrade PLS solution provides the feed for the low-grade circuit of the solvent extraction circuit.

Solvent extraction is the method used to purify the copper solution for copper refining. At Kinsevere, there are two SX trains comprising a low-grade circuit (for the low-grade PLS) and a high-grade circuit (for the high-grade PLS). This configuration has the advantage of improving copper recoveries and reducing acid consumption.

The SX process uses mixing and settling tanks to contact the pregnant acidic liquor with an organic solvent. The copper is extracted away from the aqueous phase into the organic phase, leaving most of the impurities behind. The copper bearing organic phase is then contacted with a strongly acidified aqueous solution. This causes the copper to move to the aqueous phase while the organic phase is reconstituted in its hydrogen form. The density difference between the aqueous solution and the organic solvent is used to separate the two solutions after the copper has been transferred. The copper bearing aqueous phase is then advanced to the electrowinning stage, while the organic phase, now devoid of copper, is returned to the extraction stage. The spent impure acid solution or raffinate is recycled back to the SAG mill, leach tank and CCD circuits.

In the EW process, the copper is reduced electrochemically from copper sulphate in solution and is deposited as copper metal onto a stainless steel sheet, which acts as a cathode. Electrowon copper cathodes are as pure as or purer than electrorefined cathodes from traditional smelting processes. Kinsevere has two tank houses. The EW cells run at a very high current density. Kinsevere claims the very high current density used at the refinery is the second highest in the world. Despite the high current density, the current efficiency of 91% does not appear to have fallen. When the copper deposited has achieved the desired weight, a crane is used to remove the copper cathode from the electrolytic cell. The copper is then stripped from the stainless steel cathode in an automated process. The copper cathodes are then bundled and weighed, ready for shipping. A methodical anode and cathode maintenance and cleaning regime is in place to achieve maximum current efficiencies.

There is a heap leach facility, which is now in a dormant stage. Kinsevere may look at some form of heap leach operation for the future, potentially to treat ore from additional sources, particularly lowgrade material.

Kinsevere Expansion Project (KEP)
The KEP study proposes to expand the current acid leach process to treat sulphide, transition and oxide ore, as well as recover cobalt. The Kinsevere processing facility upgrades required for the project are:
- Oxide pre-flotation circuit and leach tank modifications for 2.2 Mtpa ore treated:
1. Once Oxide Ore is exhausted, it is planned that the Oxide grinding circuit be modified (i.e. Sizer replaced with a Jaw Crusher and an additional Ball Mill be installed into the Oxide Circuit) to accommodate the processing of Sulphide Ores.
2. It has been estimated that this modified oxide circuit will be capable of processing 1.3Mtpa of Sulphide Ore.
- Oxide leach upgrades to convert to reductive leach conditions.
- Sulphide concentrator for 2.2 Mtpa ore treated.
- Roaster circuit including off-gas cleaning, acid plant and concentrate storage.
- Cobalt recovery circuit to produce high grade cobalt hydroxide.
- SX plant modifications.

Kinsevere Expansion Project, which includes the transition to the mining and processing of sulphide ore and the commencement of cobalt production, remains on track. The cobalt plant was commissioned in the fourth quarter of 2023 with cobalt hydroxide produced, containing 105 tonnes of cobalt. The new tailing storage facility was commissioned to support the cobalt plant ramp-up.

In 2023, the construction of the sulphide processing system continued with the majority of civil work completed in the fourth quarter. The site started receiving long-lead equipment and material. Mechanical and structural installation has also commenced. Progress has been made at the jaw crusher, coarse ore stockpile, SAG mill, flotation cells, thickeners and concentrator storage, as well as the main body of the roaster plant.

Moving forward, the focus will be on the ramp-up of the cobalt plant and completing the installation of the concentrator and the roaster, gas cleaning and acid plant (RGA) as well as operational readiness-related work.

Water Supply

Summary:

Kinsevere’s dewatering program is managing increasing water volumes with water either used onsite or released after appropriate quality testing. Additional drilling of boreholes in 2022 is reinforcing capacity and bringing the site additional clean water.

Production

Operational metrics

Personnel

Job Title	Name	Profile	Ref. Date
Engineering and Reliability Superintendent	Unen Ali		Aug 9, 2023
Health, Safety & Environment Manager	Junbo Feng		Aug 9, 2023
Maintenance & Engineering Manager	King Kumwimba Kalume		Aug 9, 2023
Maintenance Planner	Flair Mbala		Aug 10, 2023
Mechanical Superintendent	Augustin Mwamba		Aug 10, 2023
Mining Manager	Serge Djemo		Aug 9, 2023
Process Manager	Jean Bilali Wa Ngalu		May 13, 2024
Tailings area Manager	John Pellicer		Aug 10, 2023