Name of the Project
Mowana copper mine dense-media separation (DMS) plant.

Location
Botswana.

Client
Cradle Arc.

Project Description
An independent test report has confirmed the applicability of the DMS at the Mowana copper mine, which could increase throughput to about 2.6-million tonnes a year.

Based on the outcome of this testwork, Cradle Arc intends to progress with a development plan for the upgrades to the Mowana processing plant. The project proposes to increase production at Mowana to about 22 000 t/y of copper in concentrate.

Testwork has demonstrated that DMS preconcentration can be deployed at Mowana for all low-oxide ores (those that contain less than 25% acid soluble copper).

Testwork has revealed that:
• a mass yield of 30% to 40% copper and recovery of more than 85% can be expected;
• mill feed grades of more than 2% can be expected, nearly double the current run-of-mine;
• an optimal crushing top size of 10 mm to 12 mm should be designed with respect to the upgrade project; and
• good rejection of gangue minerals is achieved, including carbon and silicon, with more than 75% being rejected.

Potential Job Creation
Not stated.

Net Present Value/Internal Rate of Return
The project has a net present value, at a 10% discount rate, of up to $245-million.

Value
Not stated.

Duration
Not stated.

Latest Developments
Cradle Arc has secured $10-million of debt funding to support an accelerated development plan for its Mowana openpit mine and refinance part of the group’s existing indebtedness.

“Mowana has demonstrated its significant scale and, following the successful recommencement of production during 2017, our focus has now turned from the testing phase to increasing throughput and building towards profitability,” Cradle Arc CEO Kevin van Wouw has said.

To achieve this, the company has formulated an accelerated development plan that will result in four mining units being in service in the Mowana openpit, with each mining unit comprising a 75 t excavator and five 40 t articulated dump trucks. 

With the ability to operate each mining unit independently in the openpit, the accelerated development plan will enable the group to mine additional faces in the orebody simultaneously and thereby increase the volume of ore and waste mined.    

Further, the company’s new resource model captures its improved understanding of the Mowana opportunity, allowing for better returns to be achieved in the near term as the company moves from the testing and recovery phase towards steady-state operations and its goal of achieving initial nameplate capacity of 12 000 t/y of copper.

Alongside this, work continues on the definition of a maiden Joint Ore Reserves Committee-compliant reserve estimate, which will incorporate the planned process plant improvements so that, once the company has achieved initial nameplate capacity at the current plant, it can look to build production to more than 20 000 t/y through the planned DMS upgrades.

Meanwhile, additional mining equipment, including twenty 40 t articulated dump trucks, three CAT D8 dozers, two CAT374 excavators, a grader and a water truck, along with the accompanying support equipment and spares, has been delivered to site in support of the group's accelerated development plan.

Key Contracts and Suppliers
Wardell Armstrong International (Mowana resource remodelling).

On Budget and on Time?
Too early to state.

Contact Details for Project Information
Cradle Arc, tel +44 20 7499 5881.