Petra Diamonds said annual revenue rose 27 per cent to 402.7m dollars on the back of an increase in production.Production was up 21% to 2.67m carats in the year to end of June, slightly above the previously revised market guidance of 2.65m carats.The year-on-year rise was driven by output from the Finsch mine in South Afriac and Williamson mine in Tanzania.The group expects production to grow in the fiscal year of 2014 to between 2.9m and 3.0m carats.During the period, the company kept a tight rein on costs. Capital expenditure came to $201.2m, up from the previous year's $138m, in line with expectations. Cash at year end was at $26.2m, down from last year's $37.4m, while loans and borrowings grew to $147m from the previous year's $69.2m."This is another solid result for Petra, as the company continues to deliver further significant production increases and revenue growth," said Chief Executive Officer, Johan Dippenaar. "Our capital expenditure for the year reflects the ongoing roll out of our expansion plans. We remain on track to deliver on our growth plans to reach annual production of circa 5 million carats by full year 2019." Shares fell 0.26% to 117p at 13:36 on Tuesday.RD