Highlights

• MGX Resources Limited said in its September 2026 quarterly activities report that construction of the Groundrush decline has.

• MGX bought its 50 per cent stake from Northern Star in February 2026 for $50m in cash.

• Underground infill drilling of about 33,000 metres to roughly 600 metres depth is due to start in 2027.

• Away from the joint venture, MGX holds about 3,600 square kilometres of wholly owned tenure in the Central.

MGX Resources (ASX:MGX) — said it held A$408.7m of cash and investments at 30 September 2026 and is targeting a development decision for Central Tanami within 12 months.

MGX Resources Limited said in its September 2026 quarterly activities report that construction of the Groundrush decline has begun at the Central Tanami Project joint venture in Western Australia, in which it holds a 50 per cent interest. The company, which is also winding down its Koolan Island iron ore business, said it had cash and investments of $408.7m and no bank borrowings.

Groundrush decline and Tanami drilling

MGX bought its 50 per cent stake from Northern Star in February 2026 for $50m in cash. The other joint venture partner, Tanami Gold NL, shares a major shareholder with MGX. The company said it signed a $38m contract with Macmahon Underground on 31 August 2026 to build the Groundrush decline, which will run for 3.5 kilometres to a depth of about 350 metres over roughly 14 months. A blast for the main portal was scheduled for the week after the report. MGX's share of joint venture spending in the quarter was $14.7m.

The joint venture's resource stands at 31 million tonnes at 2.8 grams per tonne gold for 2.8 million ounces, of which MGX's share is 1.4 million ounces. The Jims deposit contains 2.6 million tonnes at 2.7 grams per tonne for 220,000 ounces, and Groundrush has more than 400,000 ounces of Inferred resource that the company hopes to upgrade to Indicated. During the quarter the joint venture completed 13,900 metres of reverse circulation drilling in 95 holes at Jims, finishing in mid-September, and began three diamond holes totalling 639 metres that will also support metallurgical testwork. No results from this drilling have been reported.

Underground infill drilling of about 33,000 metres to roughly 600 metres depth is due to start in 2027. MGX said a process plant would, subject to confirmation, have an initial throughput of about 1.5 million tonnes a year, and it is targeting a development decision within the next 12 months. That decision has not been made.

Koolan Island wind-down

Koolan Island produced about 43.7 million wet metric tonnes of iron ore since 2007. In July the company shipped its final four low-grade cargoes, totalling 0.3 million wet tonnes at 42.7 per cent iron. Operating cash flow for the quarter was $0.3m after $7.7m of rehabilitation costs, and the Main Pit was fully flooded to sea level on 28 October 2026.

MGX has agreed to sell Koolan to Crestlink for at least $20.2m in up-front and deferred consideration, plus up to $5m, indexed to inflation, in revenue share. Crestlink would assume remaining rehabilitation obligations that the company estimates at about $30m. Foreign investment and competition approvals have been received, and settlement is targeted for late 2026 or early 2027.

Cash and investments

Cash and investments were $408.7m, compared with $412.1m at 30 June. The company reported a net outflow of $5.1m, which included inflows of $13.2m of interest and other income, among them $9m of insurance proceeds for the October 2025 rockfall, against outflows of $14.7m on the joint venture and $3.9m of corporate costs. Claims with other insurers continue, and the amount and timing of any further receipts are uncertain.

MGX also holds an equity portfolio of about $67.0m, including 9.4 per cent of Fenix Resources, 3.8 per cent of AIC Mines and 4.6 per cent of Maronan Metals.

Other exploration and next steps

Away from the joint venture, MGX holds about 3,600 square kilometres of wholly owned tenure in the Central Tanami, where seismic and gravity modelling has identified structures that have not been drill-tested. It also holds about 1,650 square kilometres in the Edmund Basin in the Gascoyne region and obtained an A$180,000 State government exploration incentive grant after quarter end.

Upcoming events include the portal blast, the Crestlink settlement, continuing insurer discussions and the annual general meeting on 18 November 2026 in Perth.