London-listed Unicorn Mineral Resources (UMR) expects to sign legal documentation for its acquisition of a controlling stake in the Klein Aub copper mine, in Namibia, along with 5.6-million tonnes of slimes and tailings, by the end of June.

UMR in November last year signed conditional heads of terms to acquire a 75% stake in the Klein Aub mine for R26.5-million, or about £1-million. At the time, the company said it would initially target the extraction of copper and silver from the slimes and tailings when the acquisition was concluded.

A corporate reorganisation of the vendor's group in April this year delayed the initial weeks of the legal documentation drafting with the result that the process has taken longer than expected, but that work is now well advanced.

In parallel, UMR has been working to identify the optimal extraction process using European company Draslovka's glycine leaching agent. A team from UMR visited a copper mine in Zambia to assess an enhanced heap-leaching process designed for the heap-leaching materials similar to those at Klein Aub. 

This system has been running successfully at the Zambian copper mine for the last two years with good results.  This process has relatively low capital and operating expenditure requirements making it an effective solution for the tailings facility at Klein Aub, which has an estimated grade of 0.26% copper and 7.4 g/t silver. 

UMR has also been strengthening its relationships with the Namibian Ministry of Industries, Mines and Energy (MIME) following positive meetings during the fieldtrip in April. MIME has subsequently provided information on more than 150 additional tailings facilities that resulted from mining activity prior to Namibia's independence in 1990. 

These tailings facilities have left the country with a significant remediation challenge, which starts with the extraction of any remaining metals. UMR believes its expertise and technologies can be of significant value in dealing with the remediation challenge and provide further opportunities for the company in Namibia.

"The company has used the extended documentation process to bring forward work that would have been necessary post completion and so, overall, little time has been lost. We are particularly pleased with the results of the Zambian site visit and we believe that we have the right technology partners to not only extract the value from the Klein Aub tailings but also, with support from the Namibian MIME, to tackle the enormous opportunities across the country," comments UMR chairperson Paddy Doherty.