Rain City Resources signs technology agreement with Ion Source for lithium extraction

Calgary, Alberta--(Newsfile Corp. - April 17, 2026) - Rain City Resources (CSE: RAIN) ("Rain" or the "Company") is pleased to announce that it has entered into an expansive term sheet with Ion Source LLC ("Ion Source"), a Texas based technology company focused on wastewater purification. The agreement provides both parties with an initial 90-day period to finalize and execute binding definitive agreements covering a broad range of collaborative initiatives. Rain and Ion Source will jointly develop new products and technologies with a focus on DLE and critical mineral extraction by adapting Ion Source's patent published water purification cavitation -electrolysis platform (the "IS Technology").

Rain shall be granted an exclusive licensing arrangement in South America. Rain and Ion Source shall establish a jointly owned intellectual property company to develop and commercialize co-developed patents and actively promote the IS Technology across key resource jurisdictions. Our next-generation platform- Accelerated Controlled Critical Minerals Extraction (AC²ME) , will provide a patentable approach for extracting lithium and other critical minerals from brines, while also using and promoting the IS Technology for advanced water purification solutions associated with hydrocarbon and mineral extraction activities.

Deal Highlights Joint Development: Co-development of new applications derived from the IS Technology, including, but not limited to, direct lithium and critical mineral extraction. Exclusive Rights: Rain to receive exclusive rights to utilize the IS Technology for new applications in South America. Shared Intellectual Property: Creation of a jointly owned IP company to develop, manage, and license patents arising from collaborative work.

Technology Promotion: Ion Source to appoint Rain as a non-exclusive agent to introduce and promote IS Technology to resource sector companies in North and South America. Global Collaboration: Joint commercialization opportunities for co-developed technologies outside South America. Strategic Investment Rights: Rain granted a right of first refusal on any Ion Source capital raises for the duration of the partnership.

Acquisition Rights: Ion Source will provide Rain an 18 month right of first refusal on any potential sale of Ion Source following the execution of definitive agreements. Research Collaboration: Potential collaboration with the University of Calgary on process development. Regional Support: Continued strategic assistance from the Catholic University in Santiago, Chile.

CEO Commentary Benjamin Hill, CEO of Rain City Resources, commented: "After funding a successful pilot plant last year in conjunction with former partner Avonlea Lithium, Rain has remained focused on identifying an environmental and commercially scalable solution for DLE in regions where freshwater scarcity demands ultra efficient processes. Following extensive technical evaluation and discussions with multiple technology providers, we believe Ion Source offers the strongest platform from which to advance our next-generation DLE and critical mineral extraction solution." Nicholas Holbrook, CEO of Ion Source, commented: "This partnership brings together two teams that understand what it takes to deliver real solutions in the field. Rain offers deep regional knowledge and strong technical capabilities.

Together, we have a clear path to commercialize advanced water treatment and critical mineral recovery at scale through our combined platform." Next Steps With a long term, broad ranging technical solution secured, Rain will continue its engagement with partners and stakeholders in South America. With an expanded technical team working collaboratively with Dr Ian Hutcheon, Director of Rain and Professor Emeritus of Geochemistry at the University of Calgary, on refining our AC²ME process we are confident in our ability to deliver a patented commercial DLE solution. Additionally, Rain has already begun working with Ion Source on commercialising Ion Source's underlying water purification technology in South and North America.

About Rain City Resources Rain is an integrated critical mineral technology and project development company committed to addressing the environmental, social, and economic challenges of lithium and critical mineral extraction from brine. By advancing scalable, water-conscious DLE solutions, Rain is helping drive the transition to a clean energy future. About Ion Source LLP ION Source is a U.S.-based water treatment technology company commercializing a proprietary, patent-pending advanced separation platform for the purification of industrial and produced waters and the recovery of critical minerals from brines.

ION Source's technology is designed to deliver efficient, scalable, and environmentally responsible treatment of high-salinity and contaminated water streams. Applications span oil and gas produced water management, lithium and critical minerals extraction, and industrial wastewater treatment FOR FURTHER INFORMATION CONTACT: RAIN CITY RESOURCES INC. Website: www.raincityresources.com Email: info@raincityresources.com Telephone: 403-693-8004 Cautionary Statement Regarding Forward-Looking Information This news release may include certain "forward-looking statements" under applicable Canadian securities legislation. There can be no assurance that such statements will prove to be accurate, as actual results and future events could differ materially from those anticipated in such statements.

Accordingly, readers should not place undue reliance on forward-looking statements. Rain disclaims any intention or obligation to update or revise any forward- looking statements, whether as a result of new information, future events or otherwise, except as required by law. There can be no assurance that proposed operations will be successful or that the anticipated financial, economic or strategic benefits will be realized.

Neither the Canadian Securities Exchange nor its Regulation Service Provider (as the term is defined in the policies of the Canadian Securities Exchange) accepts responsibility for the adequacy of accuracy of this news release. To view the source version of this press release, please visit https://www.newsfilecorp.com/release/293093 Source: Rain City Resources Inc.