Legacy Minerals is progressing an optimised scoping study at its Mt Carrington project, leveraging a 39% increase in resource tonnes and a 69% jump in indicated resources. Results are expected in December 2026, aiming to assess the economics of a larger-scale operation.
- 39% growth in total resource tonnes to 47.9Mt
- 69% increase in indicated resources to 19.3Mt
- Optimised study assessing plant throughput beyond 1Mtpa
- May 2026 scoping study showed A$514M pre-tax NPV
- Study results due in December 2026 quarter
Optimised Scoping Study Targets Larger Scale Operation
Legacy Minerals Holdings Limited (ASX:LGM) is advancing an Optimised Scoping Study at its flagship Mt Carrington Gold-Silver Project in New South Wales, aiming to capitalise on a substantial 39% increase in resource tonnes and a 69% uplift in indicated resources since May 2026. The study, led by engineering firm Ausenco and advisory group WSP, is evaluating the potential for processing plant throughput beyond the original 1 million tonnes per annum (Mtpa) design, with results anticipated in the December 2026 quarter.
Resource Growth Underpins Expansion Potential
The July 2026 Mineral Resource Estimate (MRE) now stands at 47.9 million tonnes grading 1.0g/t gold equivalent (AuEq), containing 1.6 million ounces AuEq, comprising 714,000 ounces of gold and 35 million ounces of silver. This marks a 39% increase in resource tonnes and a 44% rise in silver ounces since the 2025 MRE that underpinned the May 2026 Scoping Study. Notably, the indicated resource category has surged 69% to 19.3Mt at 1.22g/t AuEq, providing a stronger foundation for mine planning and development.
By comparison, the May 2026 Scoping Study was based on a production target of just 10.1Mt processed at 1Mtpa, less than a quarter of the current total resource. That study delivered a pre-tax net present value at 7% discount (NPV₇) of A$514 million (US$334 million), a 38% internal rate of return (IRR), and a first-quartile all-in sustaining cost (AISC) of A$1,188 per ounce gold (US$772/oz) under spot price assumptions.
Study Scope Maintains Proven Processing Strategy
The Optimised Scoping Study updates key inputs including metal prices, concentrate payabilities, processing costs, plant ramp-up assumptions, and capital and operating cost estimates. The processing and marketing approach remains unchanged, utilising a cyanide-free flotation flowsheet to produce a saleable precious metal concentrate. Ausenco is responsible for process engineering and financial modelling, while WSP handles mine optimisation and scheduling, leveraging their experience from preparing the July 2026 MRE.
Drilling Continues to Support Resource Growth
Alongside the study, Legacy Minerals is actively drilling at the Emu copper-gold prospect and planning follow-up drilling at the Mascotte gold-silver prospect, targeting new discoveries and further resource expansion. These efforts complement the recent resource upgrade and could add to the project's scale and value.
CEO Highlights Opportunity to Enhance Project Economics
CEO Christopher Byrne emphasised the significance of the resource growth, stating that the increased resource base opens the door to assess scale economies through a larger plant and expanded production target. This could translate into higher annual metal output, longer cash flow duration, and improved project economics compared to the earlier 1Mtpa scenario. Byrne expressed confidence in the collaboration with Ausenco and WSP, anticipating a comprehensive update to shareholders upon study completion.
Bottom Line?
Legacy Minerals’ pending Optimised Scoping Study could redefine Mt Carrington’s scale and economics, but investors must await December quarter results to gauge the true impact.
Questions in the middle?
- How will increased plant throughput affect capital expenditure and operating costs?
- What production target will the Optimised Scoping Study ultimately recommend?
- Could ongoing drilling at Emu and Mascotte materially expand the resource further?