Rhyolite Ridge Project

Ioneer is advancing the Rhyolite Ridge Lithium-Boron Project in Esmeralda County in Nevada and is fully-funded to a Final Investment Decision.

The Definitive Feasibility Study is modelled on a 26 year mine life – though there is significant potential for this to increase.

It is one of two advanced lithium projects in the U.S. and is expected to be a low cost lithium producer, in part due to the valuable boron co-product.


  • 25km west of Albemarle’s Silver Peak lithium mine
  • 330km southeast of the Tesla Gigafactory near Reno
  • 530km north of Los Angeles
  • In Esmeralda County – the most sparsely populated county in Nevada
  • On Federal (Bureau of Land Management) land at an altitude of approximately 1,800m
  • In uninhabited semi-arid desert with annual rainfall averaging 10mm.

Advancement Highlights

Company History

  • In January 2023, the U.S. Department of Energy offered Ioneer a conditional commitment of up to US$700 Million, to develop the Rhyolite Ridge Project.
  • 2022
  • In February 2022, Ecopro increased its offtake agreement.  
  • In June 2022, Ioneer listed its securities on Nasdaq under an American Depository Receipt (ADR) listing. (Nasdaq ticker: IONR).
  • On July 22, 2022, Ioneer announced a binding offtake agreement with the Ford Motor Company to supply 7,000 tpa of lithium for a 5-year period from the Rhyolite Ridge Project.
  • In August 2022, ioneer signed a 5-year binding lithium offtake agreement with PPES, a joint venture between Toyota Motor Corporation and Panasonic Corporation, for 4,000 tpa of lithium carbonate.
  • In December 2022, the U.S. Bureau of Lands Management (BLM) advanced the Rhyolite Ridge Project into the final stage of federal permitting with their decision to publish the Notice of Intent in the Federal Register. This marks the start of the NEPA process.
  • 2021
  • In October 2021, Ioneer announced an agreement with Sibanye-Stillwater to develop a joint venture whereby Sibanye will contribute US$490 million for a 50% interest.
  • EcoPro Innovation Co. signs lithium carbonate offtake agreement with ioneer for its battery plant in South Korea.
  • 2020
  • In April 2020, the Company announced the results of a Definitive Feasibility Study validating the robust economics and viability of Rhyolite Ridge.
  • 2018
  • The Company changed its name from Global Geoscience to Ioneer Ltd to reflect its new focus and commitment to becoming an important producer of the materials necessary for a sustainable future.
  • In October 2018, the Company announced the results of a Pre-Feasibility Study that clearly showed that Rhyolite Ridge will be a structurally low cost and very long-life mine supplying two critical materials necessary for urbanization and energy efficiency.
  • 2017
  • Global Geoscience secured ownership of the Rhyolite Ridge Lithium-Boron Project and fully committed to its development.
  • 2016
  • The Company's strong reputation led prospectors to bring a little-known lithium-boron project in southern Nevada to Mr Rowe. He recognised that Rhyolite Ridge mineralogy was fundamentally different than other known sedimentary lithium deposits. At Rhyolite Ridge two thick sedimentary layers contain lithium and high-grade boron, and very little clay. This critical difference in why Rhyolite Ridge will become the lowest cost source of lithium in the world.
  • 2007
  • Global Geoscience listed on the ASX and one of the founders was current Ioneer Managing Director Bernard Rowe. The focus of Global Geoscience was to apply geological science and theory towards making a major greenfield mineral discovery. Primarily exploring in and around Nevada, Global Geoscience entered into several exploration partnerships with major mining companies.
  • Our Partner

    Sibanye-Stillwater is listed on the New York Stock Exchange and Johannesburg Stock Exchange and has a market capitalisation of U.S.$10 billion.

    It is one of the world’s largest primary producers of platinum, palladium and rhodium, and is also a top tier gold producer, ranking third globally on a gold equivalent basis.

    We are extremely pleased to have welcomed Sibanye-Stillwater, a leading international mining company, as a strategic partner in the Rhyolite Ridge Project.

    Sibanye-Stillwater is an excellent partner for Ioneer to jointly realize the promise of Rhyolite Ridge thanks to:

    • Its proven track record of developing and operating major mining projects including three integrated facilities in Montana
    • Its commitment to developing and maintaining an inclusive and sustainable culture, and
    • Its determination to become a major force in the battery materials supply chain.
    • This field is for validation purposes and should be left unchanged.