Mining company Piran Resources has achieved first tin production and the first bulk sale of the final tin product from its Musha and Ntunga mine, in Rwanda, is expected at the end of April, the company tells Mining Weekly.

Piran MD Ben Smit says, since the mine’s processing plant was commissioned in December 2014, the company has conducted tests on parcels of material from different parts of the area to determine the head grades of the different areas.

The Musha and Ntunga mine is under two licences because it had been previously managed by separate companies that both ceased to operate in 2010. Piran was issued a mining licence for both sites in 2012.

The two sites are contiguous and Piran operates it as a single mine, with mining operations to begin on the Musha side and, subsequently, includes material from the Ntunga side.

The mine will process tailings – left by previous Belgian miners that employed inefficient mining methods since the 1950s – in the high-grade area.

Smit explains that the area contains high-grade, underground tin deposits and, despite the Belgian miners using rudimentary mining methods which did not extract the optimum of tin equivalent, they had a profitable operation.

However, in partnership with processing plant and upgrade solutions provider Appropriate Processing Technologies, Piran has updated the technologies at the plant, such as the concentrators, so that the mining of the tailings left by the Belgian miners, with an average grade of 0.37% of tin equivalent, is profitable, Smit explains.

The grade of the tailings vary between 0.27% and 0.54% of tin equivalent, with tantalum and tungsten as by-products.

Smit says the main problem when mining tailings is that the grade varies throughout the deposit, necessitating constant testing and blending before processing can be done.

The Musha and Ntunga processing plant can process 120 t/h of rock and Smit predicts that, at full production, about 150 t/m to 180 t/m of tin will be produced.

Piran will process between three-million tons to four-million tons of tailings in the high-grade area. The tailings should take about four years to mine, after which Piran will excavate the hard rock in the area. This second phase of the project will comprise an underground mine as most of the veins are thin and are, therefore, not conducive to openpit operations.

To prepare for the second phase of the project, over the next two to three years, Piran will conduct an exploration programme of the underground veins across the hard rock.

Piran has an offtake agreement with diversified supply chain group Noble Resources International, which will buy the tin produced at the Musha and Ntunga mine.

Piran in Rwanda
Smit explains that the Rwanda government has been trying to develop the country’s extractive industry.

“The Ministry of Natural Resources and the Rwanda Development Board are doing a lot, but there are still significant challenges because they are fairly new to large-scale industrial mining.”

Smit adds that the Rwanda government has shown initiative in restarting a local smelter, which was test-run earlier this year, which Piran would be prepared to supply with tin for beneficiation.

However, he believes that, firstly, unstable power supply to the smelter could be a significant challenge to the project that aims to reintroduce beneficiation to the economy and, secondly, that the smelter could not handle all the production in the country.

The Musha and Ntunga mine will be labour intensive and will create about 350 permanent jobs when in full production. Smit says these jobs are important to stimulate the local economy, as it previously relied on illegal artisinal mining, which has been clamped down on in the area.