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Defense Metals Acid-Bake Process Yields Improved Rare Earth Element Recoveries At Wicheeda

News Release - Vancouver, British Columbia – May 31, 2022: Defense Metals Corp.

(“Defense Metals” or the “Company”) (TSX-V:DEFN / OTCQB:DFMTF / FSE:35D) is pleased

to announce the initial results of alternative Acid Bake process testwork underway at SGS

Lakefield on Wicheeda Rare Earth Element (REE) Project mineralized feed. The initial testworkshows that adoption of the Acid Bake process results in improved REE extraction, and potentially improvements in capital and operating costs.

The previous hydrometallurgical flowsheet that was included in the PEA (preliminary economic assessment 1 ) was based on a more costly and complex gangue-leach – caustic-crack process. Upon joining the team, Defense Metals’ lead metallurgical consultant, John Goode, P.Eng., recommended investigation of the acid-bake process for the Wicheeda ore, and the preliminary results show that the acid-bake process is more efficient, yielding >95% recovery of neodymium and praseodymium from flotation concentrate into a leach solution (Figure 1).

Figure 1: Selected Preliminary Acid-Bake Results

This hydrometallurgy program that started in December, which includes pilot-plant operations, will be concluded in the last quarter of 2022. It will provide data to allow a detailed design and capital-and operating-cost calculations. Updates on the test work will be provided periodically as results become available.

Luisa Moreno, President of Defense Metals commented: “We are delighted that the acid-bake process has yielded higher recoveries of rare earths and offers the potential to significantly reduce operating and capital costs, thus improving project economics and further establishing Wicheeda as a potential near-term source of rare earths.”

Ongoing tests:

● Testing of the acid-bake process started in late 2021, with over 20 tests on several

concentrate samples completed to investigate the impact of bake conditions including acid

addition, concentrate grade, and bake temperature.

● Tests continue to show that the sulphuric acid-bake approach is highly effective. Across all

tests, including those under sub-optimal conditions, the neodymium/praseodymium

extraction is 94% with better test results showing 97 to 99% extraction.

● Short-duration acid-bake pilot operations using the SGS Lakefield 165 mm diameter kiln

are ongoing.

● Pregnant leach solution from the static acid-bake tests is now being tested for impurity

removal and the precipitation of a refined rare-earth product suitable for sale.

Details of the Acid-Bake-Water-Leach (AB-WL) Process

In the AB-WL process, Wicheeda’s mineral concentrate will be treated with concentrated sulphuric acid at high temperatures (200 ̊C-600 ̊C) converting the rare earths in the minerals to water-soluble sulphates, which readily dissolve during the subsequent water leach. The leachate is then purified, and the rare-earth elements recovered by a simple precipitation process. This process requires less equipment, and involves fewer steps and circuits, as schematically presented in Figure 2. Importantly, this flowsheet is the same as that used by Lynas at its Kuantan REE production facility and by Baogang at the Bayan Obo REE recovery plants (using a bastnasite and monazite ore). Most of the world’s REE are produced by the Acid-Bake process.

Figure 2: Acid-Bake Process Flowsheet

About the Wicheeda REE Property

The 100% owned 2,008-hectare Wicheeda Rare-Earth Project, located approximately 80 km

northeast of the city of Prince George, British Columbia, is readily accessible by all-weather gravel roads and is near infrastructure, including power transmission lines, the CN railway, and major highways.

The Wicheeda Rare-Earth Project yielded a robust 2021 PEA that demonstrated an after-tax net present value (NPV@8%) of $517 million, and 18% IRR1. A unique advantage of the Wicheeda Rare-Earth Project is its ability to produce a saleable high-grade flotation concentrate. The PEA contemplates a 1.8 Mtpa (million tonnes per year) mill-throughput open-pit mining operation with 1.75:1 (waste:mill feed) strip ratio over a 19-year mine (project) life, producing an average of 25,423 tonnes REO annually. A Phase 1 initial-pit strip ratio of 0.63:1 (waste:mill feed) would yield rapid access to higher-grade surface mineralization in year one and payback of $440 million initial capital within five years. The Acid-Bake process is expected to improve upon the 2021 PEA economics.

Qualified Person

The scientific and technical information contained in this news release, as it relates to the Wicheeda Rare-Earth Project, has been reviewed and approved by John Goode, P. Eng., who is a Qualified Person as defined by National Instrument 43-101 and has provided the technical information relating to metallurgy in this news release.

About Defense Metals Corp.

Defense Metals Corp. is a mineral-exploration and development company focused on the

acquisition, exploration and development of mineral deposits containing metals and elements commonly used in the electric-power market, defense industry, national-security sector and in the production of green-energy technologies, such as, rare-earth magnets used in wind turbines and in permanent-magnet motors for electric vehicles. Defense Metals owns 100% of the Wicheeda Rare-Earth Project located near Prince George, British Columbia, Canada. Defense Metals Corp. trades in Canada under the symbol “DEFN” on the TSX Venture Exchange, in the United States, under “DFMTF” on the OTCQB and in Germany on the Frankfurt Exchange under “35D”.

For further information, please contact:

Todd Hanas, Bluesky Corporate Communications Ltd.

Vice President, Investor Relations

Tel: (778) 994 8072


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