Petra Diamonds (LON:PDL) revealed strong production in its first quarter (of the 2014 financial year) with a 25% increase to 816,735 carats.
It says it retains guidance of 3mln carats production for the full year.
Revenues in the first quarter totalled US$65.1mln, up 27%, and the company expects a boost later this month as two exceptional white stones, recovered in the period, go to tender.
Whilst diamond prices weakened briefly after the summer, Petra expects firmer trading through to the calendar year end and in the first half of 2014.
"These results demonstrate the continued delivery of growth in accordance with our stated expansion plans,” said chief executive Johan Dippenaar.
He added: "Our mines produce a significant and growing volume of the commercial, mass market goods which form the mainstay of the diamond market, but they also regularly produce high quality, and at times world-class, diamonds.
“We are delighted to have recovered a range of such special stones in our second quarter, including two exceptional white Cullinan diamonds, which we expect to generate substantial interest at our next sales tender in late November."