Name of the Project
RHA tungsten project.

Location
The project is located near Hwange, in Zimbabwe.

Client
Premier African Minerals holds 49% of RHA Tungsten, with the remaining 51% held by Zimbabwe’s National Indigenisation and Economic Empowerment Fund.

Project Description
The 1 800 ha project is divided into 50 mineable mineral blocks, of which Premier African Minerals owns ten.

The preliminary economic assessment (PEA) on the project was completed in August 2013.

The mine plan presented in the PEA consists of an openpit, followed by an underground operation, with a combined life-of-mine (LoM) of six years at a run-of-mine production rate of 192 000 t/y, or 16 000 t/m.

The underground mine produces a wolframite concentrate that is measured in metric ton units (mtu); wolframite consists primarily of ferberite, with a smaller quantity of hubnerite.

Every mtu of concentrate is equivalent to 10 kg of tungsten trioxide contained in a concentrate at about 60%.

Premier Mining has since the completion of the PEA commissioned Bara Consulting to update the financial model of the project to demonstrate the effect of the additional work that has been completed since the publication of the PEA on the product valuation. The financial model outlines a low-capital implementation strategy.

Jobs to be Created
The project boasts entirely local skills, with no expatriates employed at the mine.

Net Present Value/Internal Rate of Return
Bara’s financial model reflects a pretax net present value of $15.8-million and an annualised internal rate of return of 286%, calculated on a quarterly basis.

Value
The project preproduction capital has been reduced from $4.77-million to $4.15-million.

Duration
Operations at the mine started in August 2016.

Latest Developments
The RHA underground tungsten mine has a forecast eight-year mine life, but a resource upgrade, which is expected to conclude in the coming weeks, should “more accurately” assess the life-of-mine (LoM).

Premier African Minerals CEO George Roach has told Mining Weekly that he would like to see a combination of underground and opencast mining at the mine. “When our resource evaluation and update conclude, I will be able to take better view of this.”

In July, Premier reported that it had completed plant upgrades the project, which produced its first concentrate last year.

At this time, the screens, plant modifications and electrical reticulation works had been completed and the plant was undergoing a phased commissioning and optimisation process to achieve the expected recoveries and operational throughput.

The miner noted that wolframite concentrate from ore of the underground mine had been produced and that the throughput of the plant would steadily be increased to the plant’s design capacity of 16 t/h. RHA has a target mining rate of 8 000 t/m of tungsten.

X-ray transmission (XRT) testwork has also been conducted on bulk sample material from RHA, which has been rerun at the express direction of the equipment provider to confirm previous results. The sort achieved a near 100% recovery. Premier is reassessing the pit capacity to meet the minimum tonnage that XRT sorting will require.

Meanwhile, Roach has told Mining Weekly that Premier African Minerals still knows “very little” about the ultimate depth extensions at the RHA project beyond historical drilling. “One interesting feature is that concentrates from underground ore carry copper. It has been speculated that this may increase with depth,” he adds.

In terms of RHA’s environmental impact, he points out that during the mining of tungsten, there are no contaminants left over in the water used for the mining operation, which would usually have a negative effect on the surrounding communities.

Key Contracts and Suppliers
Bara Consulting (updated financial model).

On Budget and on Time?
Not stated.

Contact Details for Project Information
Premier African Minerals, tel +27 100 201 281 or email info@premierafricanminerals.com.