Ioneer Ltd. announced an updated Mineral Resource estimate for the South Basin at the Rhyolite Ridge Lithium-Boron Project located in Nevada, USA. The effective date for the updated Mineral Resource estimate is March 31, 2023. Highlights: Rhyolite Ridge South Basin Mineral Resource of 360 Mt containing 3.4 Mt of lithium carbonate equivalent (168% increase) and 14.1 Mt of boric acid equivalent (18% increase).

The Mineral Resource now includes both high-boron lithium mineralisation and low-boron lithium mineralisation. The previous Mineral Resource estimate only included high-boron lithium mineralisation. Demonstrates optionality around future growth opportunities including increasing lithium production with or without increasing boron production.

The March 2023 Mineral Resource lies entirely within the project boundary currently being permitted under the Mine Plan of Operation. All mineralised units remain open in three directions with approximately 60% of the South Basin remaining to be drilled, underscoring the potential for further increases in the Resource. Rhyolite Ridge is ideally placed to play a pivotal role in the electrification of transportation in the U.S. In production, it will support the rapidly developing domestic lithium battery supply chain and lead innovation and sustainability in the production of materials critical to a clean energy future.