QMines to ramp up Mt Chalmers scale with bulk concentrate test success

QMines Ltd (ASX:QML) has announced positive results from bulk flotation metallurgical test work, which significantly boosts the potential scale and economic outlook of its Mt Chalmers project in central Queensland.

The results highlight an increase in processing throughput and concentrate production, positioning the project for a more simplified and efficient operation.

Scale-up plans following successful bulk flotation tests

The bulk flotation test work, conducted on a blended composite of ores from both the Mt Chalmers and Develin Creek projects, delivered impressive recoveries and confirmed the viability of scaling up the Mt Chalmers operation from a 1 million tonnes per annum (Mtpa) to a 2Mtpa throughput.

Mount Chalmers and Develin Creek project locations and infrastructure.

The simplified flowsheet now being adopted will support a centralised critical minerals processing hub in the region, potentially enhancing the project’s overall scale and operational efficiencies.

The increase in throughput is expected to significantly boost production across key commodities, with annual copper production forecast to rise to 14,000 tonnes, gold to 25,000 ounces, zinc to 7,500 tonnes and silver to 300,000 ounces.

Metallurgical performance demonstrates strong recoveries

The flotation test work, conducted in May and June 2025, delivered superior recovery rates for base metals and precious metals, with the copper recovery reaching 98.1%, gold recovery at 88.7%, zinc at 92.6%, and silver at 88.6%. These results have affirmed the project’s ability to produce high-quality concentrates at scale while keeping processing operations simple and cost-efficient.

“These metallurgical results reinforce the case for a larger and more efficient copper and gold development in central Queensland,” said QMines executive chairman Andrew Sparke. “We’re seeing better recoveries, larger volumes of concentrate from the test work and a much simpler flowsheet — all of which translates to a faster time to mill construction.”

Simplified plant design to reduce capital and operating costs

The revised processing strategy centres around a bulk flotation approach, which presents multiple advantages over traditional sequential flotation processes.

This approach not only reduces capital expenditure (capex) due to a simpler flowsheet but also lowers operating costs (opex) by requiring fewer reagents, less power and more streamlined control systems.

Additionally, the faster construction timeline will enable earlier cash flow, a key driver for the company’s development.

Expanded mine plan with Develin Creek integration

An essential development stemming from the test work is the integration of the Develin Creek project into the overall mine plan. The addition of Develin Creek’s three deposits — Sulphide City, Scorpion and Window — enhances the scalability of the operation, increasing the processing capacity from 1Mtpa to 2Mtpa.

This expanded scale is expected to improve the project’s economics by increasing processing throughput, extending the mine life and leveraging operational synergies between the two projects.

As a result, QMines is progressing with an updated pre-feasibility study (PFS) that will reflect this increased capacity, with final results expected in the first half of 2026. In the interim, drilling programs and resource upgrades at Develin Creek and Mt Chalmers are under way.

Strategic focus on long-term, sustainable growth

With drilling rigs active across both projects, and engineering studies progressing to define the optimal development pathway, QMines is well positioned to advance its strategy of becoming a mid-tier copper and gold producer.

The combination of higher-grade ore from Develin Creek, larger processing capacity, and simplified operations presents a clear path to unlocking substantial shareholder value and long-term growth.

The company is poised to enter its most catalyst-rich phase, with key milestones set for the remainder of 2025, including the completion of resource upgrades and the drilling of the Mount Mackenzie deposit.