JOHANNESBURG (miningweekly.com) – LSE-listed Petra Diamonds’ production of 999 768 ct for the third quarter, ended March 31, was only marginally higher than the 995 905 ct it produced in the same quarter of 2016.
However, run-of-mine (RoM) production for the quarter increased 18% to 760 916 ct, with RoM grades improved owing to the ongoing ramp-up of underground expansion projects. Third-quarter tailings and openpit volumes were impacted on by unseasonably high rainfall in both South Africa and Tanzania.
Petra’s Finsch mine achieved a 23% increase in RoM production to 468 429 ct, while the Cullinan operation’s production increased 20% to 227 523 ct, mainly as a result of the 23% increase in RoM carat production as the new C-Cut Phase 1 mining area continuing to ramp up as planned.
RoM production from the Cullinan C-Cut is expected to reach around one-million tonnes for the full year.
Meanwhile, Koffiefontein's production decreased 3% to 13 184 ct, impacted on by a slower-than-anticipated start-up post the production shutdown in the previous quarter.
Despite this “disappointing” performance, production was expected to improve over the next two quarters to levels exceeding 20 000 ct a quarter.
Attributable production from the joint venture Ekapa Mining operation delivered 185 144 ct, with surface operations negatively impacted by rainfall. Treatment of underground RoM ore increased compared with previous quarters following the commissioning of the RoM crushing circuit in the combined treatment plant, with a further increase in RoM throughput expected during the fourth quarter.
Production at Petra’s Williamson mine, in Tanzania, decreased 9% to 51 402 ct, as the final stages of commissioning of the new mill section were undertaken. Unseasonably high rainfall during the period adversely impacted both access to blasted RoM tonnes in the openpit and the handling and treatment of the resultant wet ore.