Name of the Project
Rhyolite Ridge lithium/boron project.

Location
Nevada, US.

Project Owner/s
In September 2021, Sibanye-Stillwater entered into an agreement with ioneer to establish a joint venture (JV) company with respect to Rhyolite Ridge. Following the satisfaction or waiver of all conditions precedent, Sibanye-Stillwater will acquire a 50% interest in the JV, with ioneer maintaining a 50% interest and retaining the operational management responsibility for the JV.

Project Description
A definitive feasibility study (DFS), completed in April 2020, has placed Rhyolite Ridge as the (single) most attractive project for the production of lithium carbonate, lithium hydroxide and boric acid globally.

The lithium and boron mineral resource is estimated at 146.5-million metric tonnes, including an ore reserve of 60-million metric tonnes – an increase in the reserve from the previous estimate of 280% over the 26-year life-of-mine (LoM).

The mine plan comprises almost entirely reserve material, with nearly 50% of that being proven ore reserves.

The resource remains open in three directions, allowing for a potential extension to the LoM.

The project will mine 2.5-million metric tons a year of ore over the LoM to produce about 20 600 t/y of lithium carbonate, or about 22 000 t/y of lithium hydroxide and 174 400 t/y of boric acid, on average.

Potential Job Creation
Not stated.

Net Present Value/Internal Rate of Return
The project has an after-tax net present value, at an 8% real discount rate, of $1.265-billion, and an unlevered internal rate of return of 20.8%, with a payback of 5.2 years from the start of first production.

Capital Expenditure
The DFS estimates that the total capital expenditure to complete the project will be $785-million, including an 8% contingency.

This represents an increase of $186-million from the prefeasibility study.

The US Department of Energy has said it will lend ioneer up to $700-million to develop the mine.

Planned Start/End Date
ioneer expects to start production in 2025 to support urgent requirements for battery materials in the US.

Latest Developments
Environmental and Indigenous groups filed a lawsuit on October 31 challenging the US Interior Department's approval of ioneer's Rhyolite Ridge, the first domestic source of the battery metal to be permitted by US President Joe Biden's administration.

In a lawsuit filed in federal court in Las Vegas, groups including the Center for Biological Diversity argued the project posed an existential risk to the rare wildflower Tiehm’s buckwheat and could drive it to extinction.

They said the mine would also adversely impact on groundwater, springs, wetlands, air quality, cultural resources and wildlife habitats, and would transform a remote part of rural Nevada into an industrial complex.

The groups said the Interior Department's Bureau of Land Management (BLM) approved the mine without ensuring that it would not jeopardise the wildflower or unduly impact on the environment in violation of the National Environmental Policy Act, the Federal Lands Policy and Management Act, and the Endangered Species Act.

ioneer received approval for the mine on October 24, 2024, following a more-than six-year review process during which regulators, ioneer and conservationists tussled over the fate of Tiehm’s buckwheat.

The permit was issued amid a flurry of recent moves by Biden administration officials to support critical minerals production and offset China's market dominance.

The permit also unlocked a $700-million loan from the US Department of Energy, as well as a $490-million equity investment from Sibanye-Stillwater to fund the project.

The Interior Department said when it approved the mine that it had taken numerous steps to protect the ecosystem near the mine site.

Key Contracts, Suppliers and Consultants
Fluor (DFS).

Contact Details for Project Information
ioneer, tel +61 2 9922 5800.
Sibanye-Stillwater, tel +27 11 278 9600 or email ir@sibanyestillwater.com.