Petra Diamonds Limited projected rough diamond output of 3 million carats for the fiscal year that ends on June 30, 2014, which is at the high-end of earlier guidance and represents a 12 percent increase from fiscal year 2013. Petra also expects rough diamond prices to remain firm, with guidance supported by constrained supplies, a firmer U.S. market and continued growth in China. The guidance for weighted average price per carat was highest at Petra's Koffiefontein diamond mine at $518 and lowest at the Finsch mine at $113. Cullinan's guidance came to $139 per carat, Kimberley underground was $301 per carat, Helam was $145 per carat and Williamson at $254 per carat.

In an updated guidance document published today, Petra added that it anticipates long-term production to reach 5 million carats by fiscal year 2019. Following the announcement and a conference call with analysts, shares in the company were maintaining a 2 percent gain for the day on the London Stock Exchange at 127.8 pence. Petra's shares are up 30 percent from one year ago.

Petra anticipates that its operating costs would remain controlled during this fiscal year, but certain cost categories such as labor and electricity were expected to increase higher than the average consumer price index for South Africa due to mining inflation and the weakening rand, resulting in increases associated with imported cost components.

Petra's capital expenditures (capex) for expansion across its operations in South Africa rose 8 percent from previous guidance to $157 million (ZAR 1.55 billion) for fiscal year 2014, due to timing differences in capex and detailed planning revisions at Cullinan, Koffiefontein and Kimberley underground.

The maximum draw on debt facilities for the fiscal year is anticipated to occur in the fourth quarter (April through June), but remain within the current debt facilities, according to the company.