More than 40 firms processing minerals had shut by last month
More than 200,000 jobs have been lost in the Democratic Republic of Congo amid a collapse in mineral prices as a result of the global economic downturn.
There are fears the job losses could reach 300,000 by the end of this month.
Officials said the cost of producing minerals like cobalt and copper was greater than the price the commodities are fetching on world markets.
More than 40 firms processing minerals had shut by last month, mainly in the southern Katanga province.
The BBC's Thomas Fessy in DR Congo says with about half of the world's cobalt and 4% of the copper, Katanga is the richest province in DR Congo.
Provincial Minister of Mines Barthelemy Mumba Gama said the province generates nearly half of the country's revenue.
He said that the situation could be saved if the central government agreed to relieve the tax burden in the mining sector.
DR Congo has long been popular with mining companies, with its rich supplies of cobalt, copper, tin, radium, uranium, diamonds and coltan, a vital ingredient for mobile phones.