First-ever diamond drilling beneath the flooded historic Mt Chalmers open pit has commenced, testing extensions to the Central Queensland copper-gold deposit.

It’s the feature of the QMines quarterly report.

A purpose-built floating platform is being used to reach mineralisation beneath the pit lake, which conventional land-based rigs could not access for decades.

The pontoon program forms part of a 10,000m campaign, supporting a Definitive Feasibility Study now fully funded through a $15 million package.

Related: QIC gets behind Mount Chalmers development

QMines Limited (ASX:QML) Executive Chairman Andrew Sparke said: “This is one of the most exciting drilling programs we’ve undertaken at Mt Chalmers because it has the potential to create value in two ways.”

The program aims to grow the resource at depth while converting Inferred material into Ore Reserves for a larger or longer mine plan.

The company’s June quarterly report, released on 31 July, confirmed the strategic funding deal with the Queensland Investment Corporation’s Critical Minerals and Battery Technology Fund.

Main image: The flooded Mt Chalmers pit where a purpose built floating platform is being used to reach mineralisation.

The package comprised a $5 million equity investment and a $10 million royalty, lifting cash to $14.4 million at quarter end.

QMines also completed its maiden 73-hole, 9,798m drilling program at the Mount Mackenzie gold-silver project, where Mineral Resource estimation had commenced.

Mount Mackenzie results included 24 metres at 1.19 grams per tonne gold and 13.3g/t silver from 71 metres, confirming mineralisation below shallow historic holes.

At Mt Chalmers, the opening metallurgical hole returned 18 metres at 2.7g/t gold and 1.7 per cent copper from 54 metres, including a metre at 20.3g/t gold.

Six geotechnical holes were completed for 538.3 metres, while metallurgical drilling and the company’s largest-ever Woods Shaft program got underway.

The 39-hole, 7000m Woods Shaft program targets an expanded resource across ten targets, adding to combined project resources of about 20 million tonnes.

Mt Chalmers already holds an Ore Reserve of 9.6 million tonnes, grading 0.65 per cent copper and 0.48g/t gold.

The 2024 Pre-Feasibility Study returned a $373 million net present value and 54 per cent internal rate of return over a 10.4-year mine life.

Most metal prices have risen since that study, generating projected life-of-mine revenue of $1.64 billion for the flagship project near Rockhampton.

Mr Sparke said the coming months would deliver ‘a strong pipeline of news flow and several exciting catalysts for our shareholders’.