(IDEX Online) - Petra is to re-open its Williamson mine, in Tanzania, more than a year after it was put on on care and maintenance amid the first Covid lockdowns and unprecedented low rough prices.The mine, a quarter-owned by the Tanzanian government, has now reportedly secured overdraft funds to resume production at full capacity. It halted operations when the per carat price of the rough it sold last March fell to $131, from an average of $208. At the time Petra blamed "depressed and opportunistic bidding".Prof Shukrani Manya, deputy minister for minerals, this week said: "The local banks have agreed to finance the operations for three months. This could take the company into the next phase of diamond sales."Williamson was established back in 1940, and has been among the oldest continuously operating diamond mines in the world.Richard Duffy, CEO of UK-listed Petra Diamonds, said when the mined was closed last year: "Given the unprecedented trading conditions, we are taking all steps necessary to preserve the company's liquidity position in order to withstand this very difficult period until market conditions improve."We remain committed to protecting the ongoing viability of our operations, to the benefit of all our stakeholders." Pic shows Williamson mine