Rio Tinto Diamond Sales $326 Million in H1

RTD's sales leaped 77.2% as rough diamond prices surged upwards in H1 2010. Above, underground work at Diavik

Multi-commodity miner Rio Tinto reported a sharp rise in earnings across the board in the first half of 2010. Diamond sales by the company totaled $326 million in the period, a 77.2 percent increase from the prior year.

Rio Tinto posted record underlying earnings of $5.85 billion for the group, 125 percent above 2009 first half, the miner reported Thursday.

Rio Tinto produced 7.1 million carats during the six month period, a 4.7 percent increase. The clear difference between the rise in production and the rise in earnings highlights the resurgence in rough diamond prices over the past year.

Earnings before interest, taxes, depreciation and amortization totaled $75 million for the miner’s diamond business and net earnings of $34 million compared with a $56 million loss in the first half of 2009.

At the company’s Diavik mine in Canada, held with Harry Winston Diamonds, underground development at a cost of $787 million ended and the underground mine produced its first ore at the end of March.

Development of the underground mine at Argyle, however, a $1.5 billion project, has been slowed to critical development activities. The project was to extend the mine life to mid-2019.

In addition to the 60 percent holding in Diavik and the fully owned Argyle mine in Australia, Rio Tinto's diamond interests include a 77.8 percent stake in the Murowa mine in Zimbabwe.