Famed Cullinan mine banks on big diamonds to drive down debt

By Emma Rumney and Barbara Lewis

CULLINAN, South Africa (Reuters) - The owner of one of the world's most famous diamond mines could be about a decade away from clearing its multi-million-dollar debts, in a sign of the struggles facing an industry assailed by synthetic rivals and uncertain demand.

Petra Diamonds bought Cullinan in 2008, aiming to breathe new life into the South African mine renowned for yielding the largest rough gem diamond ever found - 3,106 carats - and being the world's main source of rare blue diamonds.

The London-listed miner, which acquired Cullinan from industry leader De Beers, borrowed heavily to revamp the facility and began mining a new section of ore last July.

Petra told Reuters its debts from the mine stood at around 65 percent of its overall $650 million in borrowing, which would represent about $420 million.

Cullinan's general manager Juan Kemp added that it could take "between five and 10 years" from the opening of the new section to clear the debts related to the mine. That goes beyond the 2022 maturity of Petra's bond notes.

Petra's chief executive Johan Dippenaar later said that, though 60 percent of total group capital and sustaining expenditure had been allocated to Cullinan, the repayment of the notes is based on cash flows from all four of Petra's mines.

Cullinan accounted for around a third of the company's diamond sales revenue in 2018.

The company says Cullinan has been profitable every year since it acquired the mine and it expects to generate free cash flow this year - a target it had hoped to reach in 2017 before being derailed by strikes and construction delays - and start reducing its debts.

Kemp said one thought kept him awake at night: "When will we get that next big stone?"

But he added that the company was in a good position, with a new mine that was exceeding production expectations and keeping costs in line.

Ben Davis, mining analyst at Liberum, said the diamond prices Petra had achieved were below market expectations.

"Everyone is very much hoping, for the sake of the equity holders and debt holders, it will deliver more higher-quality stones," he added.

Jacques Breytenbach, Petra's finance director, said pricing at Cullinan was variable from one period to the next, and that the market tended to be weaker at the end of the calendar year due to destocking. An increase in diamond tenders in the second half of Petra's financial year would make a big difference to cash generation, he said.

The miner's difficulties reflect in part the problems facing the industry - which often takes years to recover huge investments - including new competition from synthetic diamonds and sluggish demand, especially for small stones.