Queensland explorer QMines (ASX: QML) has confirmed the potential for an open pit operation to 160 metres depth at its flagship Mt Chalmers project following the recent completion of a pit optimisation study.
The study was undertaken by Western Australian company Minecomp and based on the fourth mineral resource estimate for the project which sits at 11.3 million tonnes grading 0.76% copper, 0.42 grams per tonne gold, 4.52g/t silver, 0.22% zinc and 0.08% lead for 85,600 tonnes copper, 153,240 ounces gold, 1.6 million ounces silver, 24,400t zinc and 9,600t lead.
It determined that Mt Chalmers has the potential to support the extraction of 7.1Mt at a head grade of 1.5% copper equivalent, potentially delivering 48,000t copper, 137,500oz gold, 1.3Moz silver, 26,000t zinc and 12,000t lead net of mining dilution and processing losses.
Robust mining operation
QMines managing director Andrew Sparke said the study has strengthened the company’s view that a robust mining operation could be developed at Mt Chalmers.
“The results of this pit optimisation study are testament to the significant amount of work completed by our team in such a short period of time,” he said.
“The delivery of four resources at Mt Chalmers in just 18 months shows the motivation of our team and the time and cost advantages of the owner-operator exploration model.”
He said QMines will conduct additional metallurgical test work to advance the project towards a feasibility study and the delivery of a maiden ore reserve statement.
It will also investigate expansion opportunities to include underground mining and satellite deposits.
Well-preserved system
The Mt Chalmers deposit is a well-preserved volcanic-hosted massive sulphide (VHMS) system containing copper, gold, zinc, lead and silver.
The geometry implies a flat-lying asymmetrical mound intersecting higher grade copper-gold massive sulphides proximal to the centre of the deposit and high-grade lead-zinc-silver in massive sulphide and exhalite mineralisation distal to the centre of the deposit.
Similar metal zoning has also been observed in the disseminated zone beneath the mineralisation where copper-gold grades are typically higher in the centre and lead-zinc-silver grades are higher at greater depths.
QMines’ optimised pit captures the zones of higher-grade mineralisation and extends them to a depth of approximately 160m.
It utilises massive and semi-massive sulphide mineralisation identified over the past 18 months of drilling.
