JOHANNESBURG (miningweekly.com) – Multicommodity miner Mwana Africa on Monday reported that gold production at its Freda Rebecca gold mine, in Zimbabwe, declined by 25% quarter-on-quarter to 13 072 oz for the three months ended December, owing to a mill being temporarily unavailable as a result of engineering downtime and shutdowns.
However, the company’s 75%-owned subsidiary Bindura Nickel Corporation saw a 76% quarter-on-quarter increase in nickel-in-concentrate sales to 2 651 t from its Trojan operation, in Zimbabwe.
"Operationally, this has been a mixed quarter for the company. We are very pleased with the progress at Trojan and this demonstrates the robustness of the asset. Freda Rebecca, however, had a difficult quarter due to reduced mill availabilities,” Mwana CEO Kalaa Mpinga said.
The company explained that the mill at Freda Rebecca was undergoing modifications that would lead to improved throughput.
“Production [at Freda Rebecca] was also impacted by a drop in head grade owing to the temporary cessation of mining at its openpit operations,” Mwana said, adding that this issue was not expected to be a factor in the next quarter.
Further, despite the lower head grade, plant recoveries benefitted from the availability of all three leach tanks, resulting in improved leaching efficiencies with an increase to 84.9% from 83.6% in the last quarter, while all-in sustaining costs increased by 22.6% from $1 053/oz to $1 291/oz, mainly as a result of lower gold production in the quarter.
The mine’s pilot plant for tailings retreatment had also been completed and had entered the commissioning phase.
Further, at the Trojan mine all-in sustaining costs had increased from $10 390/t to $11 819/t as a result of the continued production ramp-up and the start of the shaft redeepening.
Mwana added that the mine’s quarterly revenue increased by 74%, at $24.5-million, owing to higher sales volumes.
KLIPSPRINGER DIAMOND MINE
Following the agreement signed between the Klipspringer joint venture, comprising Mwana and black economic-empowerment company Naka Diamond Mining, to retreat the Marsfontein slimes dams at the Klipspringer mine, in Limpopo, South Africa, mining and treatment operations started on October 7.
To date the slimes retreatment programme had produced 6 114 ct at an average price $22.75/ct.
Despite lower than expected throughputs during commissioning, the fine diamonds recovered demonstrated the feasibility of the initiative, Mwana said.
“The proceeds from diamond sales will contribute to the care and maintenance costs at Klipspringer,” Mpinga added.
The Klipspringer plant was currently operating on three shifts a day, with steady-state production of 22 560 t/m planned from February onwards.