Combined production for the three-month period slid 52% to 22,678oz, bringing the London-domiciled company's output to date to 102,113oz and putting it somewhat short of its previously reduced guidance of 180,000-200,000oz. The estimate had been previously cut from 210,000-230,000oz owing to work issues at Youga.

New Liberty output fell 57% over the prior period to 8,059oz due to heavy rainfall that flooded the main pit, causing a pit wall collapse and ramp failure.

At Youga, gold production totalled 14,619oz, a 6% decrease on the second quarter because of a security incident which hampered mining fleet availability. Early in August the company said an armed group of artisanal miners overran the camp to steal ore from the mine's stockpile.

"Following the transition to contractor mining at New Liberty and Youga earlier this year, both mines have experienced operational issues that adversely affected our mining rates and gold production performance in the quarter," said CEO Serhan Umurhan.

He expects the final quarter of 2019 to see an uptick in operational performance at both operations. Given the end of the wet season at New Liberty, the company expects materially enhanced productivity in the near term despite the recent pit-wall failure.

Meanwhile, a further 15 trucks, six excavators, a rock drill and further auxiliary equipment will be available at Youga later this week at the mining contractor's cost, which could result in an uplift in production during the current quarter.

Avesoro shares trading on the LSE (AIM:ASO) have halved in value over the past 12 months, dropping another 3.5p to 89p on Thursday, which gives it a market value of £74 million.