PERTH (miningweekly.com) – ASX-listed junior Blackthorn Resources has suspended opencut operations at the Perkoa zinc mine, in Burkina Faso, it reported on Friday, citing resource underperformance, weaker metal prices and “unacceptable” openpit financial results.

Earlier this week, joint venture (JV) partner GlencoreXstrata also downgraded the Perkoa ore reserve to 4.9-million tonnes, grading 9.9% zinc, 0.2% lead and 41 g/t silver.

Underground mining, processing and shipping activities were continuing.

Blackthorn told shareholders that it was now undertaking an intensive due diligence to verify and constructively challenge GlencoreXstrata’s review results, with the objective of committing to a final plan for the project by the end of March.

The business plan review provided by GlencoreXstrata considered a range of scenarios for the project, including placing the zinc mine on care and maintenance, in response the current trading conditions.

Opportunities for cost reductions were also being identified in all areas of operation, including mining, processing, administration and logistics.

“It has been important for Blackthorn management to address these issues directly with GlencoreXstrata. We will look to constructively challenge the work with a view to delivering the best possible result,” said Blackthorn CEO Mark Mitchell.

In parallel with the work being done on the business plan, Blackthorn was also in discussions with GlencoreXstrata to resolve the funding requirements for Perkoa, including the $30-million working capital advanced by the major.

Mitchell added that the company’s intention remained to resolve the outstanding issues around Perkoa by the end of March, to allow the company to fully focus on the Kitumba copper project prefeasibility study and the planning required to take the Kitumba project forward.