Rand Refinery is restarting smelting operations and boosting refining as South Africa’s COVID-19 lockdown starts to ease, with the speed of the ramp-up dependent on gold mines’ production, the chief executive of the refinery said on Thursday.

Rand, which produces between 250 and 280 million tonnes of refined gold a year, shut its smelter and scaled down gold refining for the duration of the lockdown, which began on March 27 and was only beginning to ease slightly from May 1.

Chief Executive Praveen Baijnath said the refinery, deemed an essential service authorised to continue despite the lockdown, has been operating at 50% capacity, and is currently operating at “50 to 60%”.

“The degree of ramp up will be determined by the volumes of gold that will emerge from the South African mines in the coming weeks and months,” he told Reuters.

Most of South Africa’s gold mines – which include the world’s deepest, Mponeng – were forced to temporarily shut down in the lockdown, but President Cyril Ramaphosa on April 16 authorised mines to start up again at up to 50% capacity.

Deep-level gold mines – where social distancing is all but impossible – remain a thorny issue, with mining unions demanding adequate regulations over COVID-19 be put in place before they return to work.

Rand Refinery’s smelter, which processes low grade gold concentrates, was restarting on Thursday, Baijnath said, having been under care and maintenance since March 27.

Rand Refinery joins the ranks of gold refineries in Switzerland firing up almost all operations again after the country relaxed its lockdown measures.

A private company, Rand Refinery’s shareholders include some of South Africa’s biggest gold miners: AngloGold Ashanti with a 42.4% stake, Sibanye-Stillwater with 33.15%, DRDGOLD which owns 11.3%, Harmony Gold with 10% and Gold Fields which holds 2.76%.