Aim-listed Cradle Arc’s share price tumbled 28% on Wednesday after the company lowered its 2018 production guidance and detailed the operational difficulties that it faced at its 60%-owned Mowana copper mine, in Botswana.

The mine’s revised guidance for 2018 is to produce 4 000 t of copper in the second half, of which only 1 000 t will be produced in the third quarter and 4 000 t in the final quarter of the year.

The company explained that, during the current quarter, the drilling contractor experienced a three-week breakdown and that an additional contractor had to be appointed. The miner has also introduced a third mining unit at the openpit operation, but said that mechanical issues had resulted in lower-than-expected machine availabilities, thus impacting further on ore volumes delivered to the processing plant.                                                                                                                                                      

The lower volume of available ores being delivered to the processing plant, alongside sporadic interruptions to processing owing to plant outages, resulted in 45 224 t of ore being milled in July, leading to a lower than forecast 292 t of contained copper being produced for the month. In mid-August, further intermittent breakdowns have been experienced, including a technical failure in one of the main programmable logic controllers within the milling circuit, which resulted in further considerable periods of processing downtime.

Cradle Arc said that it would introduce the fourth mining unit to start operations in the fourth quarter, which would enable it to ramp up to full steady state production.

Shares in the company fell by 28% from 4.2p to 3.5p each, before recovering some ground to trade at 3p a share late in the afternoon.

The share price drop comes despite the news that Cradle Arc had recruited two senior industry executives to its board, including Zimbabwean Roy Pitchford as nonexecutive chairperson to replace Toby Howell, who will resign to pursue other interests.

Pitchford has 25 years of experience in the Southern African mining industry and has held the position of CEO or MD for Vast Resources, Central African Gold, African Minerals, Cluff Resources Zimbabwe, Delta Gold Zimbabwe, African Platinum and Zimbabwe Platinum Mines. He is a past president of the Chamber of Mines of Zimbabwe.

The miner also appointed Michael Golding, who has over 20 years of corporate and project finance experience, to its board as a nonexecutive director.