Mountain Province Diamonds Inc. provided its first quarterly production report Oct. 24 for the new Gahcho Kué diamond mine in the Northwest Territories. From the Aug. 1 start of ramp-up production to Sept. 30, the plant produced 198,000 carats of diamonds from roughly 130,000 metric tons of ore.

Mountain Province, which holds a 49 percent joint venture interest in Gahcho Kué, owns roughly 97...