Ioneer Ltd has announced the entry into strategic non-binding letters of intent (LoI) with the Korea Overseas Infrastructure & Urban Development Corporation (KIND) and Hyundai Engineering Co. Ltd to advance the development of the Rhyolite Ridge lithium-boron project in the US.
KIND is the Republic of Korea’s specialised public institution mandated by the Ministry of Land, Infrastructure and Transport (MOLIT) to facilitate and invest in overseas infrastructure and public-private partnership projects, while Hyundai Engineering is a leading Korean and international engineering, procurement and construction company.
The project holds significant strategic value for both the Republic of Korea and the United States, Ioneer states. Rhyolite Ridge hosts the only known lithium-boron reserve in North America, one of two globally, and the only project of its kind in active development. The parties intend to formalise their cooperation through the execution of Memorandums of Understanding expected in July 2026.
Since 2016, Ioneer has invested more than $220 million in Rhyolite Ridge and has completed more than 70% of its advanced engineering work. Ioneer is targeting a final investment decision for the second half of 2026, with first commercial production expected in 2029. Once operational, Rhyolite Ridge will process ore into final products entirely on-site and create and support 275-300 permanent on-site positions during operations. It also plans to leverage autonomous haulage technology.
Bernard Rowe, Managing Director, Ioneer, said: “Rhyolite Ridge has been a decade in the making – through ongoing partnerships, permitting and financing. Working with trusted Korean partners with a track record of on-time and on-budget delivery brings us closer to breaking ground and delivering urgently needed lithium and boron. We’re delighted to work with KIND and Hyundai Engineering and look forward to what we’ll accomplish together.”
Chris Soeung Kim, Director of plant business division, KIND, said: “KIND, as a specialised PPP investment institution under the MOLIT, has been actively advancing investments in US energy, infrastructure and critical minerals projects. We view this project as a major milestone that will further strengthen bilateral cooperation and deepen the strategic partnership between the Republic of Korea and the United States.”
Seung Dong Lee, Head of Process Plant Business Execution Office, Hyundai Engineering, said: “Across the metrics that matter most – permitting, construction readiness, and long-term supply certainty – Rhyolite Ridge stands apart from other critical mineral projects. This letter of intention to participate in the engineering, procurement and design reflects our commitment to pursuing shared interests, securing a reliable critical minerals supply chain for the industries we serve and our confidence in Ioneer’s leadership.”
The entry into these strategic LOIs strengthens Ioneer’s relationship with the Republic of Korea. In 2021, Ioneer signed a binding offtake agreement with EcoPro Innovation, a world-leading high-nickel cathode producer.
The LOIs are non-binding and do not create legally enforceable obligations on the part of KIND and Hyundai Engineering to invest in or otherwise support the development of Rhyolite Ridge. There can be no certainty that legally binding arrangements will be entered into.