Magrathea and TETRA Achieve Technical Breakthrough in Production of Magnesium from Arkansas Brine
San Francisco, CA, 16 June 2026 - Magrathea, a technology company building the US’s only new magnesium metal smelter, through its Arkansas Magnesium joint venture with partner TETRA Technologies Inc., an energy services and solutions company, announced production of the first >99.9% pure primary magnesium metal meeting ASTM (American Society for Testing and Materials) B92 specifications from Smackover brine produced in Lafayette County, Arkansas.
The magnesium metal was produced using Magrathea’s proprietary electrolytic process from Smackover brine sourced from TETRA’s acreage in Lafayette County, Arkansas. The resulting metal exceeded 99.9% purity and met ASTM B92 specifications for primary magnesium. The achievement represents an important de-risking milestone for Arkansas Magnesium’s Commercial Phase 1 development program and provides further validation of the joint venture’s technical and commercial strategy.
"Producing ASTM-spec magnesium metal from Arkansas brine is a major technical milestone for our team and validates the core premise behind Arkansas Magnesium," said Alex Grant, CEO of Magrathea. "For decades, America has relied on foreign magnesium supply despite having world-class domestic resources. This result demonstrates that Southwest Arkansas can become the foundation for rebuilding a secure, competitive, and scalable US magnesium industry, and that the Arkansas Magnesium joint venture is the obvious solution to the nation’s magnesium supply challenge."
“Successfully producing ASTM-spec magnesium metal from our Smackover resource highlights the quality of Arkansas’ critical mineral reserves and the strength of our partnership with Magrathea,” said Brady Murphy, CEO of TETRA. “By combining TETRA’s resource base and operational expertise with Magrathea’s innovative process technology, we are advancing a practical path toward domestic magnesium production and strengthening America’s critical mineral supply chain.”
“This achievement demonstrates that Arkansas continues to be a national leader in critical minerals, advanced manufacturing, and industrial innovation,” said Hugh McDonald, Secretary of Commerce of Arkansas. “The partnership between TETRA and Magrathea is transforming Arkansas resources into strategic materials that strengthen our economy, create high-quality jobs, and support American supply chain security.”
In November 2025, Magrathea and industrial chemicals producer TETRA Technologies, Inc. (NYSE: TTI) signed a term sheet to form a joint venture called Arkansas Magnesium to evaluate the technical and commercial benefits of a magnesium extraction plant in Southwest Arkansas at TETRA’s Evergreen chemical campus. The JV partnership business model de-risks plant finance and reduces operating costs by leveraging TETRA’s energy, land, supply chain, and operational capabilities. In March 2026, Magrathea and TETRA finalized the JV operating agreement establishing the joint venture, and engineering work is underway on the Arkansas Magnesium’s Commercial Phase 1 plant.
Magnesium is the “gateway metal” used across the defense industrial base and economy. It is critical for aerospace with 400 pounds of it used in a single Blackhawk helicopter, is vital in every aluminum alloy, and is essential for primary steelmaking. Magnesium is consumed in making several other critical materials including titanium for aerospace, hafnium and zirconium for nuclear, beryllium for electronics, and amorphous boron for kinetics. Magnesium is designated a critical mineral by the Department of Energy, Department of War, and Department of the Interior.
About Magrathea
Magrathea is a technology company founded in California that has developed a new generation of electrolytic process for making clean, secure magnesium metal from seawater and brines. Magnesium supply underpins trillions of dollars of trade and national security is impossible without it and Magrathea is the category leader in re-building ex-China supply of the critical material. Magnesium supply underpins trillions of dollars of trade. National security is impossible without it. Magrathea is the category leader in rebuilding ex-China supply of the critical material. For media inquiries, please contact media@magratheametals.com.
About TETRA
TETRA Technologies, Inc. is an energy services and solutions company focused on developing environmentally conscious services and solutions that help make people's lives better. With operations on six continents, the Company's portfolio consists of Energy Services, Industrial Chemicals, and Critical Minerals. In addition to providing products and services to the oil and gas industry and calcium chloride for diverse applications, TETRA is expanding into the low-carbon energy market with chemistry expertise, key mineral acreage, and global infrastructure, helping to meet the demand for sustainable energy in the twenty-first century.
Cautionary Statement Regarding Forward Looking Statements
This press release includes certain statements that are deemed to be forward-looking statements that TETRA intends to be included within the safe harbor protections provided by the federal securities laws. These forward-looking statements include statements concerning the possible formation of a joint venture between Magrathea and TETRA to re-start a magnesium metal defense industrial supply base at TETRA’s Evergreen Project site in Southwest Arkansas, the completion of TETRA’s Bromine production plant near Stamps, Arkansas, production levels of bromine, lithium and magnesium at the Evergreen Project site, TETRA’s ONE TETRA 2030 strategy, possible government support for TETRA’s future commercial plans and the amount of investment or number of jobs to be created by the Evergreen Project and joint venture. These forward-looking statements are based on certain assumptions and analyses made by TETRA in light of its experience and its perception of historical trends, current conditions, expected future developments, statements made by Magrathea and other third parties and other factors it believes are appropriate in the circumstances. Such statements are subject to numerous risks and uncertainties, many of which are beyond the control of TETRA. Factors which may cause actual results to differ materially from current expectations include the factors described in the section titled “Risk Factors” contained in TETRA’s most recent Annual Report on Form 10-K, as well as other risks identified from time to time in its reports on Form 10-Q and Form 8-K filed or furnished with the Securities and Exchange Commission. Investors should not place undue reliance on forward-looking statements. Each forward-looking statement speaks only as of the date of the particular statement, and TETRA undertakes no obligation to update or revise any forward-looking statements, except as may be required by law.