De Beers is ramping up diamond sales to cash in on a recovery from last year's slump.
The company last week sold $610 million of uncut stones at its second auction of the year, 12 percent more than a January offering that was already bigger than expected.
"Rough-diamond demand continues to show signs of improvement as excess inventory has continued to work through the system in recent months," Philippe Mellier, chief executive officer of the Anglo American Plc unit, said in a statement.
"However, we remain mindful of the need for a cautious approach as the recovery continues."
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