Highlights

  • Equity and procurement partnership discussions for Rhyolite Ridge delayed to the December quarter after counterparties require more time for internal approval processes.
  • Cash of US$54.6 million provides 12.8 quarters of estimated funding; Goldman Sachs advising on the JV process.
  • Core drilling restarts in October 2026 at Rhyolite Ridge; BLM has approved a plan for exploratory drilling in the South Basin covering approximately 10 acres.
  • DOE loan of US$996 million closed in January 2025; a Ninth Circuit legal appeal is pending with a decision expected by mid-2027.

The partnering timeline has slipped again. Ioneer (ASX:INR) told the ASX on 23 October 2026 that its Rhyolite Ridge lithium-boron equity partnership process, targeted for the September quarter, had moved into the December quarter because the parties with whom it is in advanced discussions require more time for internal approvals. The project itself — and its federal funding — remain intact.

Who Is Involved and Where Talks Stand

In July 2026, Ioneer announced a memorandum of understanding with KIND Capital for a partial equity stake in the Rhyolite Ridge project and a separate procurement MOU with Hyundai Engineering. Both MOUs remain active; no terms have been disclosed. Goldman Sachs is advising the company on the JV process. Ioneer says it is in discussions with multiple parties and that the delay is due to counterparty approval timelines rather than any deterioration in the terms or interest level.

The Project Itself

Rhyolite Ridge is a combined lithium-boron deposit in Esmeralda County, Nevada, designed to produce battery-grade lithium carbonate and boric acid from the same open-pit ore body. The DOE Loan Programs Office closed a US$996 million loan to Ioneer in January 2025, covering a significant portion of the project's estimated capital cost. A final investment decision timing is described as 'to be advised', deferred pending the JV completion. Site core drilling is restarting in October 2026 after a seasonal break; the Bureau of Land Management has separately approved a plan to drill roughly 10 exploratory holes in a 10-acre area of the South Basin.

Legal Uncertainty

The Ninth Circuit Court of Appeals has an appeal pending over whether the Tiehm's buckwheat — an endangered flower native to the Rhyolite Ridge valley — was properly assessed in the project's environmental permitting. The original permitting upheld the project. The appeal was filed by the Center for Biological Diversity; a decision is expected by mid-2027. If the appeal succeeds, Ioneer may need to redesign aspects of the mine plan to accommodate the plant's habitat. The company considers a constructive outcome more likely.

Defence-Grade Boron Carbide

Separately, Ioneer has advanced a prefeasibility study for a boron carbide facility in Utah, designed to produce 10,000 tonnes per year of 99.9% purity boron carbide for defence applications including nuclear reactor shielding, body armour and control rods. No investment decision has been made for this facility; it is at the study stage.