Rio Tinto’s diamond production reached 3.534 million carats in the third quarter of 2011, in line with its output one year earlier, the company reported.

Production at Rio Tinto’s wholly-owned Argyle mine in Australia fell 5 percent to 2.302 million carats, while its 60 percent share of production at the Diavik mine in Canada increased 8 percent to 1.160 million carats. Output at the Murowa mine in Zimbabwe, in which Rio Tinto owns a 78 percent stake, grew 71 percent to 80,000 carats.

During the first nine months of the year, Rio Tinto’s diamond production fell 18 percent to 8.766 million carats. The company expects its share of production to reach 13 million for the full year, which would be 6 percent below output in 2010.