Ioneer (NASDAQ: IONR) secures KIND and Hyundai LOIs for Rhyolite Ridge
Filing Impact
Filing Sentiment
Form Type
6-K
Rhea-AI Filing Summary
Ioneer Ltd has entered into strategic, non-binding letters of intent with Korea’s public infrastructure investor KIND and Hyundai Engineering to help advance its Rhyolite Ridge Lithium-Boron Project in Nevada, described as the only known lithium-boron reserve in North America in active development.
Ioneer has invested more than $220 million in the project since 2016 and completed over 70% of advanced engineering. The company is targeting a Final Investment Decision in the second half of 2026, with first commercial production expected in 2029. Updated economics released in October 2025 forecast annual production of 27,800 tonnes of lithium hydroxide and 135,500 tonnes of boric acid.
Rhyolite Ridge is expected to create and support 275–300 permanent onsite jobs once operational and benefits from a US$996 million loan closed with the U.S. Department of Energy’s Office of Energy Dominance Financing in January 2025 and prior offtake agreements with Ford, Prime Planet Energy & Solutions, and EcoPro Innovation. The LOIs do not yet create binding obligations for KIND or Hyundai Engineering.
Positive
- None.
Negative
- None.
Insights
Non-binding Korean LOIs add strategic support to an already de-risked U.S. lithium-boron project.
The Rhyolite Ridge project already has key de-risking elements: a US$996 million DOE loan, final federal permits, and over $220 million invested with more than 70% of advanced engineering complete. The new letters of intent bring a Korean state-backed investor and a global EPC contractor into the frame.
Because the LOIs are explicitly non-binding, they mainly signal interest and potential future involvement rather than committed capital or contracts. If formal memorandums of understanding are executed, KIND could support financing, while Hyundai Engineering may participate in engineering, procurement, and design work.
The combination of anticipated Final Investment Decision in the second half of 2026 and first production targeted for 2029 sets a long development runway. Future disclosures on binding agreements with KIND or Hyundai Engineering and confirmation of project financing beyond the DOE loan will be important to understanding the project’s ultimate capital structure and execution risk.
Key Figures
Project investment to date: $220 million
Engineering completion: More than 70%
DOE project loan: US$996 million
+5 more
8 metrics
Project investment to date
$220 million
Invested in Rhyolite Ridge since 2016
Engineering completion
More than 70%
Advanced engineering work for Rhyolite Ridge
DOE project loan
US$996 million
Loan from U.S. DOE Office of Energy Dominance Financing closed January 2025
Lithium hydroxide output
27,800 tonnes per annum
Target annual lithium hydroxide production from October 2025 updated economics
Boric acid output
135,500 tonnes per annum
Target annual boric acid production from October 2025 updated economics
Permanent onsite jobs
275–300 positions
Expected onsite roles during Rhyolite Ridge operations
Final Investment Decision target
2H 2026
Planned timing for Rhyolite Ridge FID
First production target
2029
Expected start of commercial production at Rhyolite Ridge
Key Terms
letters of intent, Final Investment Decision, offtake agreement, tonnes per annum, +2 more
6 terms
letters of intent financial
"announced the entry into strategic non-binding letters of intent (“LOI”) with the Korea Overseas"
A letter of intent is a preliminary written agreement that outlines the main terms and mutual expectations for a planned transaction—such as a sale, merger, partnership, or financing—before the final legal contracts are signed. Think of it as a detailed handshake or a rough recipe: it shows serious intent and sets the roadmap for due diligence and negotiations, but it often leaves key details open and does not guarantee the deal will close, so investors should treat it as a strong signal rather than a certainty.
Final Investment Decision financial
"Ioneer is targeting a Final Investment Decision for the second half of 2026"
A final investment decision is the point at which a person or organization chooses to move forward with a particular project or purchase after reviewing all the necessary information and options. It is like deciding to buy a house after considering all the costs, benefits, and alternatives. This decision is important because it determines whether and when the investment will be made, impacting future financial plans and outcomes.
offtake agreement financial
"In 2021, Ioneer signed a binding offtake agreement with EcoPro Innovation"
A contract in which a buyer commits to purchase a set portion or percentage of a producer’s future output—such as minerals, energy, agricultural goods, or manufactured products—often over a multi‑year period. It matters to investors because it creates predictable sales and cash flow, reduces the risk of unsold inventory, and can make projects easier to finance; think of it like pre‑selling future harvests or securing long‑term customers before production begins.
tonnes per annum financial
"increased annual lithium hydroxide and annual boric acid production to 27,800 tonnes per annum (tpa) and 135,500 tpa"
Office of Energy Dominance Financing financial
"Rhyolite Ridge closed a US$996 million loan with the DOE’s Office of Energy Dominance Financing in January 2025"
public-private partnership projects financial
"to facilitate and invest in overseas infrastructure and public-private partnership projects"
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 6-K
REPORT OF FOREIGN PRIVATE ISSUER
Pursuant to Rule 13a-16 or 15d-16 of the
Securities Exchange Act of 1934
For the month of June 2026
Commission File Number: 001-41412
ioneer Ltd
(Translation of registrant’s name into English)
Suite 16.01, 213 Miller Street
North Sydney, NSW, 2060, Australia
(Address of principal executive offices)
Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.
Form 20-F ☒ Form 40-F ☐
EXHIBIT INDEX
The following exhibits are filed as part of this Form 6-K:
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Exhibit
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Description
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99.1
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Press release
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SIGNATURE
Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto
duly authorized.
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ioneer Ltd
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(registrant)
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Date: June 23, 2026
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By:
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/s/ April Hashimoto | |
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Name:
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April Hashimoto | ||
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Title:
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Chief Financial Officer |
Exhibit 99.1
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Ioneer Secures Strategic Letters of Intent with
KIND and Hyundai Engineering to Advance
Rhyolite Ridge Lithium-Boron Project
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•
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The Korea Overseas Infrastructure & Urban Development Corporation (KIND) and Asia’s leading engineering firm have signed non-binding letters of intent to commit to Rhyolite Ridge, advancing the
path to a Final Investment Decision.
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23 June 2026 – SYDNEY, Australia — Ioneer Ltd (“Ioneer” or “Company”) (ASX: INR, NASDAQ: IONR) announced the entry
into strategic non-binding letters of intent (“LOI”) with the Korea Overseas Infrastructure & Urban Development Corporation (“KIND”), the Republic of Korea’s specialized public institution mandated by the Ministry of Land, Infrastructure and Transport (“MOLIT”) to facilitate and invest in overseas infrastructure and public-private partnership projects, and Hyundai Engineering Co. Ltd. (“Hyundai Engineering”), a leading Korean and international engineering, procurement and construction company, to advance the development of the
Rhyolite Ridge Lithium-Boron Project (“Project” or “Rhyolite Ridge”).
The Project holds significant strategic value for both the Republic of Korea and the United 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 formalize 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. In October 2025, Ioneer released updated project economics which
halved processing time and increased annual lithium hydroxide and annual boric acid production to 27,800 tonnes per annum (tpa) and 135,500 tpa, respectively.
“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,” said Bernard Rowe, Managing Director, Ioneer. “We’re delighted to work with KIND and Hyundai
Engineering and look forward to what we’ll accomplish together.”
“KIND, as a specialized PPP investment institution under the MOLIT, has been actively advancing investments in U.S.
energy, infrastructure, and critical minerals projects,” said Chris Soeung Kim, Director of plant business division, KIND. “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.”
“Across the metrics that matter most – permitting, construction readiness, and long-term supply certainty – Rhyolite Ridge stands apart from other critical mineral projects,” said Seung
Dong Lee, Head of process plant business execution office, Hyundai Engineering.” 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.”
“Securing domestic critical minerals is an economic imperative. These letters of intent from KIND and Hyundai Engineering reflect the sophistication and strength of Rhyolite Ridge,” said
James Calaway, Ioneer Executive Chairman. “We are now one step closer to a Final Investment Decision and the construction of this once-in-a-generation asset for U.S. critical minerals production.”
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.
—ENDS—
About Ioneer
Ioneer Ltd. is an emerging lithium–boron producer and the 100% owner of the Rhyolite Ridge Lithium-Boron Project. Rhyolite Ridge is one of only a small number of lithium-boron ore deposits
globally and a linchpin project in Nevada’s burgeoning Lithium Loop.
To learn more about Ioneer, visit www.Ioneer.com/investors or join our online communities on X, Facebook, LinkedIn, Instagram and YouTube.
About KIND
The Korea Overseas Infrastructure & Urban Development Corporation (KIND) is a specialized public institution established under the Ministry of Land, Infrastructure and Transport
(MOLIT) of the Republic of Korea. KIND is mandated to support Korean companies in advancing overseas infrastructure and public-private partnership (PPP) projects by providing equity investment, structured financing, and project
development support.
KIND operates across a broad range of sectors including transportation, energy, urban development, and critical minerals, in partnership with
multilateral development banks, commercial banks, governments, and private developers. As a dedicated PPP investment institution, KIND plays a central role in expanding Korea’s overseas infrastructure footprint while advancing bilateral
economic cooperation with partner nations.
For more information, visit www.kindkorea.or.kr.
About Hyundai Engineering
Hyundai Engineering is evolving into a technology-driven energy solutions provider, expanding beyond traditional EPC services into the full energy value chain—from project development and
financing to operations.
Building on its strong foundation in global plant engineering, the company delivers end-to-end plant services from FEED to EPC, while continuously executing complex industrial and
infrastructure projects and strengthening its position in advanced industrial facilities.
In response to the global energy transition, Hyundai Engineering is accelerating its expansion into low-carbon and next-generation energy sectors, including LNG, solar power, and
nuclear. The company is actively advancing key future technologies such as SMRs, hydrogen production, and carbon capture, while also growing new businesses in electric vehicle charging and modular construction.
Through these initiatives, Hyundai Engineering is transforming into a comprehensive energy and infrastructure company, creating sustainable value across the entire lifecycle of
projects and positioning itself at the forefront of the global energy transition.
Investor Relations
Chad Yeftich, Ioneer USA Corporation
Investor Relations
ir@ioneer.com
+1 775 993 8563
Media Relations
FGS Global
ioneer@fgsglobal.com
FAQ
What did Ioneer (IONR) announce about the Rhyolite Ridge project?
Ioneer announced strategic, non-binding letters of intent with KIND and Hyundai Engineering to advance its Rhyolite Ridge Lithium-Boron Project. These potential partners could support financing and engineering, adding to an already permitted, DOE-backed project in Nevada with substantial engineering work completed.
How advanced is Ioner’s Rhyolite Ridge Lithium-Boron Project?
Rhyolite Ridge is relatively advanced, with more than $220 million invested since 2016 and over 70% of advanced engineering completed. The project has its final federal permit and a US$996 million DOE loan, positioning it for a Final Investment Decision targeted in the second half of 2026.
What production levels does Ioneer (IONR) target at Rhyolite Ridge?
Updated project economics released in October 2025 increased expected annual output to 27,800 tonnes of lithium hydroxide and 135,500 tonnes of boric acid. These quantities reflect Ioneer’s plan to process ore into final products entirely onsite as part of a large integrated operation.
When does Ioneer expect Final Investment Decision and first production?
Ioneer is targeting a Final Investment Decision for Rhyolite Ridge in the second half of 2026, with first commercial production expected in 2029. This timeline follows completion of remaining engineering, securing full project financing, and progressing construction activities at the Nevada site.
Are the KIND and Hyundai Engineering agreements with Ioneer binding?
No. The letters of intent with KIND and Hyundai Engineering are expressly non-binding and do not create legally enforceable obligations to invest in or support Rhyolite Ridge. The parties aim to formalize cooperation through memorandums of understanding, but there is no certainty binding arrangements will be completed.
What existing support and offtake agreements does Ioneer have for Rhyolite Ridge?
Rhyolite Ridge benefits from a US$996 million loan from the U.S. Department of Energy’s Office of Energy Dominance Financing and a final federal permit. Ioneer has offtake agreements with Ford Motor Company, Prime Planet Energy & Solutions, and Korea’s EcoPro Innovation to supply future lithium products.