After operating 30 consecutive days operating at 90% of designed capacity, Monument Mining (TSXV:MMY) has declared its Selinsing sulphide gold treatment plant to have reached commercial production.
The mine and mill are located in Pahang State, Malaysia, about 160 km north of Kuala Lumpur. Concentrate production averaged 79 t/d, considered satisfactory given the variability of the transition ore processed.
Monument noted, however, that flotation gold recovery was somewhat inconsistent due to the high clay content of the freshly mined transition ore and the processing of stockpiled ore mixed with oxides. Gold recovery averaged 61.4% for the 30-day period, although daily rates of over 80% were recorded.
To improve recovery, the reagents are being optimized with particular attention to the addition of soda ash for pH control, potassium amyl xanthate as a collector, and sodium hexametaphosphate as a slimes depressant. The issues with the flotation air blowers have been resolved.
Frequent failure of the pressure filter cloths continues to be an issue, said the company. Replacement filter cloth and filter plates have been ordered, but cleaning of the cloths and plates has improved overall efficiency.
The first phase of mining the Buffalo Reef BRC2 and BRC3 pit is continuing. Both transition and fresh ore have been delivered to the run-of-mine leach pad.
The Selinsing mine has proven and probable reserves of oxide, transition, and sulphide ores of 5.7 million tonnes grading 1.45 g/t gold and containing 267,000 oz.