JOHANNESBURG (miningweekly.com) – A mechanical failure in a secondary crusher at dual-listed Aureus Mining’s New Liberty gold mine, in Liberia, has temporarily halted gold production as processing activities have been suspended.

The company said in a statement that its operational team was working with its engineering, procurement and construction management contractor DRA, which had mobilised to site to assess the damage and repair the secondary crusher, and specialist technicians from the secondary crusher's original-equipment manufacturer (OEM).

Following an initial assessment by the OEM technician, all required tools, spares and ancillary equipment were sourced and were currently being expedited to the mine to allow the OEM to undertake the repair work.

The OEM expected to have the secondary crusher fully operational by October 31.

To restart production as quickly as possible, a mobile crusher, with a capacity of 200 t/h was sourced in-country and was being transported by road from Yekepa to New Liberty to cover the intervening downtime period and allow for crushing and stockpiling operations to continue.

The temporary crusher was expected to arrive at the mine by October 23.

Following the repair of the secondary crusher, the mobile crusher would be retained to provide additional flexibility during the continued ramp-up of operations.

The company believed the temporary shutdown would not severely impact production levels, but could halt gold production for up to two weeks.

During this time, the company planned to continue with mining operations to increase ore stockpiles, while taking the opportunity to undertake other preventive maintenance activities across the process plant that were scheduled to be undertaken later in the year.

During the process of commissioning and ramping up the New Liberty process plant, Aureus made eight shipments of gold doré, resulting in sales of about 10 000 oz of gold.

"The team at Aureus has reacted quickly to the mechanical failure of the secondary crusher, which happened last week. Though this is a challenging development during what are the early stages of the ramp-up of the New Liberty gold mine to commercial production, we believe it will result in only a few days of lost gold production,” Areus CEO David Reading said.

Financial services provider GMP Europe analyst Brock Salier commented that, while the shutdown was “clearly disappointing”, a two-week outage for a secondary crusher repair was relatively minor.

“While issues with hard-to-replace parts, such as the mill motor, or hard-to-remedy sections of the plant, such as the ball mill alignment, can take many weeks to remedy, this repair appears relatively straightforward.

“It is fortuitous that a mobile crusher is available in-country, a fringe benefit of weak iron-ore markets. This can replace the secondary crusher, allowing carbon-in-leach processing ahead of the repair, and potentially increasing mill throughput thereafter to 'catch up' ounces,” he pointed out.