SYDNEY, Jan 10, 2026, 16:58 AEDT — Market closed.
- Northern Star shares last closed at A$24.72, up 0.49% on the day.
- CEO Stuart Tonkin told the ASX the hit to FY26 cost guidance is “not yet known” as the miner works through December-quarter disruptions.
- Investors now look to Jan. 22 quarterly results and the Feb. 12 half-year report for updated costs and guidance.
Northern Star Resources said it still cannot quantify the impact of weaker December-quarter gold sales on its annual cost guidance, in a letter to the Australian Securities Exchange dated Jan. 8 and signed by CEO Stuart Tonkin. The miner also detailed the timing of a key plant breakdown at its Kalgoorlie Consolidated Gold Mines (KCGM) operation, saying the primary crusher failed completely on Dec. 23 and was recommissioned on Jan. 5 after running below target throughput for weeks.
Northern Star shares (ASX:NST) last closed at A$24.72 on Friday, up A$0.12, after a choppy start to the year that has kept traders glued to guidance and plant performance. The stock has ranged between A$23.67 and A$25.90 so far in 2026, and it is still well below mid-December highs around A$27.65. 1
The disclosure comes after Northern Star cut its FY26 production guidance to 1.6 million-1.7 million ounces from 1.7 million-1.85 million ounces, citing a softer December quarter. It reported preliminary December-quarter gold sales of about 348,000 ounces and said lower sales across its Kalgoorlie, Yandal and Pogo centres were expected to hurt cost performance, with a revised cost outlook to come alongside the quarterly report later this month.
Gold prices edged down on Friday, with spot gold slipping 0.2% to $4,469.03 an ounce, under pressure from a firmer U.S. dollar and index-related flows, although it was still set for a weekly gain of more than 3%, Reuters reported. That matters for Australia’s big gold producers because revenue moves with bullion, while many operating costs do not. 2
For Northern Star, the immediate question is whether the December-quarter problems are contained. The ASX letter adds colour on the crusher episode, but it does not give the number investors want: a clear, updated cost range.
The next hard catalyst is close. Northern Star will release its December-quarter results pre-open on Thursday, Jan. 22, and will host a conference call at 9:00 a.m. AEDT led by Tonkin alongside CFO Ryan Gurner and COO Simon Jessop, the company said.
After that, the company has flagged its FY26 half-year results for Thursday, Feb. 12, according to its investor calendar. 3
But the risks have not gone away. If repair work and variability at KCGM drag into the March quarter, or if outages at sites like Jundee and Thunderbox persist, the revised production range could still prove ambitious and costs could overshoot.
