Metals Exploration halts Runruno production, blames illegal mining

(Sharecast News) - Metals Exploration said on Thursday that gold production at its Runruno mine in the Philippines had been temporarily deferred for around six weeks following cyanide contamination affecting the site's BIOX processing circuit.

The AIM-traded company said the contamination originated from upstream water supplies impacted by illegal mining activity and from ore delivered from small-scale mining tunnels in Stages 5-6, where cyanide had been used by illegal miners.

It said the BIOX circuit was drained, cleaned and re-inoculated, but bacteria levels were unable to recover fully until additional sources of contamination were identified.

New monitoring procedures were being implemented to prevent future incidents, with production expected to return to planned levels within two weeks.

Metals Exploration said no amendment to its full-year 2025 production guidance of 70,000 to 75,000 ounces was required, though output was now likely to be at the lower end of the range.

"We are disappointed that we have had to temporarily defer ore processing operations at Runruno due to the contamination impacting the BIOX circuit," said chief executive Darren Bowden.

"However, we are pleased to have found the causes as to why this contamination has taken place, and are implementing additional monitoring processes to minimise the impact at present, as well as in the future."

The company stressed that the deferred output would be recovered later in the mine's life and that the incident would not have long-term operational impacts.

At 1202 BST, shares in Metals Exploration were down 4.32% at 11.62p.

Reporting by Josh White for Sharecast.com.

Metals Exploration