Magrathea
Magrathea is a US-based industrial technology company producing high-purity magnesium metal via an electrolytic process from seawater and brines, serving defense, aerospace, aluminum, steel, and nuclear customers. It operates an Oakland pilot facility and is constructing an Arkansas commercial-scale plant via a TETRA Technologies joint venture.
- Company typePrivate
- Founded2021
- HeadquartersSan Francisco, United States
- Headcount11–50
- GTM typeB2B
- OfferingHardware or Manufacturing
What Magrathea does
Magrathea Metals Inc. is a US-based, venture-backed industrial technology company founded in 2021 and headquartered in San Francisco, California. The company is developing an electrolytic process to produce high-purity magnesium metal from seawater and brines, positioning itself as the only newly-built magnesium smelting capacity in the United States following the 2021 closure of US Magnesium and addressing an estimated domestic consumption of approximately 100,000 metric tons per year, of which roughly 85-90% is currently sourced from China. Its core technology is a proprietary magnesium chloride electrolyzer that has demonstrated over 99.9% purity per the ASTM B92 standard, with a claimed near-zero emissions profile compared to traditional thermal smelting processes that emit 15-20 metric tons of CO2 per metric ton of magnesium produced.
Magrathea operates a pilot facility in Oakland, California for technology development and demonstration, and in December 2025 formed a joint venture—Arkansas Magnesium—with TETRA Technologies to build a 75-million-pound-per-year commercial plant at the Evergreen Project in Southwest Arkansas, with first-phase plant engineering underway and operations targeted by the end of 2027. The company launched its next-generation magnesium chloride electrolyzer at the Oakland pilot in May 2025 and subsequently achieved a technological breakthrough producing high-purity magnesium from Smackover brine in 2026. Target end markets are the US defense industrial base (missile and defense products), aerospace manufacturers (aircraft components requiring 99.95%+ purity), aluminum and steel producers (alloying and desulfurization), and nuclear energy customers.
The company pursues a B2B/B2G enterprise field-sales motion targeting defense contractors, aerospace OEMs, and strategic industrial sectors, with the US Department of Defense/Department of War serving as both anchor customer and major funder. Magrathea has secured $19.6 million in Defense Production Act Title III grant funding (2023) and an additional $28 million DoD investment supporting the Arkansas project, alongside $10 million in seed capital (June 2023, co-led by VoLo Earth and Capricorn Investment Group) and a $24 million Series A (March 2026, co-led by Resource Technology Capital and Balerion Space Ventures), bringing total backing to over $100 million. Revenue is not yet generated at commercial scale and pricing is not publicly disclosed, as the company remains in pre-commercial pilot operations ahead of the 2027 Arkansas plant startup.
Magrathea firmographics
Firmographics- Name
- Magrathea
- Legal name
- Magrathea Metals Inc.
- Website
- https://magratheametals.com
- Company type
- Private
- Founded year
- 2021
- Operating status
- Operating
- Headcount range
- 11–50 employees
- Short description
- Magrathea is a US-based industrial technology company producing high-purity magnesium metal via an electrolytic process from seawater and brines, serving defense, aerospace, aluminum, steel, and nuclear customers. It operates an Oakland pilot facility and is constructing an Arkansas commercial-scale plant via a TETRA Technologies joint venture.
- Ownership category
- akta.pro rank
Magrathea industry classification
Industry- Product category
- Industrial Magnesium Metal Production
- NAICS
- Nonferrous Metal (except Aluminum) Smelting and Refining (331410), Nonferrous Metal (except Aluminum) Production and Processing (3314)
- SIC
- Metal Mining (1000), Primary Smelting & Refining Of Nonferrous Metals (3330)
- akta.pro primary industry
- Magnesite & Magnesium Minerals Mining (IMAKAGAN)
- akta.pro secondary industry
- Metal Melting & Secondary Smelting/Refining (Recycled Feedstock Producers) (EUAIAJAJ)
Keywords
Where Magrathea is headquartered
LocationHeadquarters
- HQ city
- San Francisco
- HQ country
- United States
- HQ region
- North America
Offices3 records
Markets served
Magrathea business model
Business model- GTM type
- B2B
- Offering type
- Hardware or Manufacturing
- Cost components
- Technology or R&D, Infrastructure, Personnel, Supply Chain, Operations
Revenue model
- Magnesium Metal Sales: Revenue from producing and selling magnesium metal extracted from seawater and brines to industrial customers in aerospace, defense, aluminum production, steelmaking, and nuclear sectors.
Go-to-market motion1 record
Distribution channels1 record
Marketing channels1 record
Magrathea product offering
Product offeringCore offering
Magrathea produces carbon-neutral magnesium metal from seawater and brines using a proprietary electrolytic magnesium chloride process, achieving 99.9%+ purity per ASTM B92 with near-zero emissions. The company operates a pilot facility in Oakland, California, and is scaling commercial production through the Arkansas Magnesium joint venture with TETRA Technologies, targeting 75 million pounds of annual capacity by the end of 2027 to supply defense, aerospace, aluminum, steelmaking, and nuclear customers.
Product overview
Magrathea is a technology company developing carbon-neutral magnesium production technology from seawater and brines using an electrolytic process. The company's primary offering is its proprietary electrolytic magnesium production technology, which is being advanced through pilot operations at its Oakland, California facility and scaled through the Arkansas Magnesium joint venture with TETRA Technologies. The company is building what it describes as the United States' only new magnesium metal smelter, targeting critical industrial sectors including aerospace, defense, aluminum production, steelmaking, and nuclear applications. The company has launched a next-generation magnesium chloride electrolyzer and is developing a Commercial Phase 1 plant in Arkansas with engineering work currently underway.
Differentiator
Problem solved
Functional benefit
Products and services
- Magnesium Metal (from seawater and brines)
- Next-Generation Magnesium Chloride Electrolyzer
Quantifiable outcome
- Near-zero emissions vs 15-20 metric tons CO2 per metric ton magnesium
- +2 more outcomes
Companies that use Magrathea
Customer profileSegments4 records
Ideal customer profiles4 records
Magrathea technology and API
TechnologyTechnology focussed Yes
API detail
- Has API
- No
- API docs
- API detail
Core technology
AI maturity
App detail
Feature3 records
Magrathea partnerships and signals
Strategic signalPartnerships
One partnership is on record.
- TETRA TechnologiescoreJoint venture to develop domestic magnesium production at TETRA's Evergreen Project in Southwest Arkansas. The project leverages TETRA's bromine facility and Evergreen brine assets alongside Magrathea's electrolytic technology. First-phase plant engineering commenced with target production of 75 million pounds of magnesium annually by end of 2027. Magrathea has secured Defense Production Act Title III funding from Department of War for Commercial Phase 1.
Scale indicators9 records
Recent moves5 records
Expansion highlights6 records
Magrathea competitors and assessment
Company assessmentBroad incumbents
- Dead Sea Magnesium (Israel Chemicals/ICL Group): Israel-based primary magnesium producer extracting from Dead Sea brines — directly analogous feedstock source to Magrathea's Smackover/Evergreen brine plans. A relevant incumbent demonstrating commercial viability of brine-based electrolytic magnesium at industrial scale.
- Norsk Hydro: Norwegian metals major that has historically been one of the Western world's largest primary magnesium producers (via its Porsgrunn plant). A broad incumbent in primary magnesium and the larger nonferrous metals space, and a benchmark for what scaled Western magnesium production looks like.
- Magnesium Elektron (Luxfer MEL Technologies): A division of Luxfer Holdings and one of the world's largest magnesium alloy and products manufacturers, with global plants. A broader incumbent in the magnesium value chain serving aerospace, defense, and automotive end markets.
Emerging players
- MP Materials: US-domiciled producer of rare earth materials backed by DoD funding. Comparable as a strategically supported domestic critical-mineral producer building onshore supply against Chinese concentration, though focused on rare earths rather than magnesium.
- Phoenix Tailings: Massachusetts-based startup developing zero-emission electrochemical refining of critical metals including magnesium and rare earths from tailings and brines. A closely comparable emerging player using similar electrolytic, low-emissions refining technology targeting domestic critical-mineral supply.
- Alliance Magnesium: Canadian developer of a serpentine-tailings-to-magnesium process. A peer in the 'Western, non-China' primary magnesium category, using a different feedstock (mine tailings) but targeting the same strategic supply gap.
Direct peers
- Latrobe Magnesium: Australian-listed developer of a magnesium production plant in Victoria targeting fly-ash/red-mud feedstock. A direct peer in the Western primary magnesium race, pursuing a similar strategy of establishing non-Chinese supply using novel feedstock processes.
- TETRA Technologies: Magrathea's JV partner in Arkansas Magnesium and operator of the Evergreen bromine/brine asset. While primarily a brine/chemicals producer rather than a magnesium producer, TETRA controls the feedstock infrastructure critical to Magrathea's commercial pathway and is therefore a structurally important peer/partner.
- US Magnesium: Historically the only primary magnesium producer in the United States, operating the Great Salt Lake brine-based facility until its 2021 shutdown. The most direct predecessor to Magrathea's planned domestic magnesium smelter, and the company Magrathea is most explicitly positioned to replace.
Others
- POSCO (Magnesium Division): South Korean steelmaker with magnesium production capacity and strategic interest in light-metal supply for EVs and batteries. Relevant as a large, integrated producer that could become a customer, competitor, or strategic partner as Magrathea scales.
Market position
Strengths4 records
Weaknesses4 records
Competitive moat4 records
Key risks5 records
Key highlights6 records
Customer concentration
Magrathea social profiles
Digital presenceMagrathea financial estimates
Financial estimateRevenue estimate
Valuation estimate
Magrathea leadership team
Management profileNumber of profiles
Profiles4 records
Magrathea subsidiaries and ownership
Company hierarchySubsidiaries1 record
Magrathea funding detail
Funding detailFunding overview
Funding rounds3 records
Investors19 records
Funding detail is available on the Subscription and Enterprise plan.Contact sales →
Magrathea M&A and investment
M&A and investmentM&A
Investments
M&A and investment is available on the Subscription and Enterprise plan.Contact sales →
Frequently asked questions about Magrathea
What does Magrathea do?
Magrathea produces carbon-neutral magnesium metal from seawater and brines using a proprietary electrolytic magnesium chloride process, achieving 99.9%+ purity per ASTM B92 with near-zero emissions. The company operates a pilot facility in Oakland, California, and is scaling commercial production through the Arkansas Magnesium joint venture with TETRA Technologies, targeting 75 million pounds of annual capacity by the end of 2027 to supply defense, aerospace, aluminum, steelmaking, and nuclear customers.
Is Magrathea a public or private company?
Magrathea is a private company. It is classified as venture growth investor backed and is currently operating.
When was Magrathea founded?
Magrathea was founded in 2021. It employs 11 to 50 people.
Where is Magrathea based?
Magrathea is headquartered in San Francisco, United States, in the North America region.
How does Magrathea make money?
One revenue line is on record: magnesium Metal Sales.
Who are Magrathea's main competitors?
Broad incumbents on record are Dead Sea Magnesium (Israel Chemicals/ICL Group), Norsk Hydro and Magnesium Elektron (Luxfer MEL Technologies). Emerging players are MP Materials, Phoenix Tailings and Alliance Magnesium. Direct peers are Latrobe Magnesium, TETRA Technologies and US Magnesium. POSCO (Magnesium Division) is listed as an others.
Does Magrathea have an API?
No public API is recorded for Magrathea.
What industry is Magrathea in?
Magrathea's product category is Industrial Magnesium Metal Production. Its primary akta.pro industry code is IMAKAGAN, Magnesite & Magnesium Minerals Mining, with a secondary code of EUAIAJAJ, Metal Melting & Secondary Smelting/Refining (Recycled Feedstock Producers). Its NAICS code is 331410 and its SIC code is 1000.