MYM Rift Basin Resources Corporation

MAYEN MINERALS LTD. (TSX VENTURE: MYM) (the "Company" or "Mayen"). Further to the Company's news release dated May 26, 2010, Mayen is pleased to announce that the Company has entered into a definitive agreement dated July 9, 2010 (the "Option Agreement") among Ivonne Boileve Romero ("Romero"), Navial Holdings S.A. de C.V. ("Navial Holdings"), Navial Mineria S.A. de C.V. ("Navial Mineria" and together with Romero and Navial Holdings, the "Optionors") and Minmay S.A. de C.V. ("Minmay"), a wholly-owned indirect subsidiary of the Company, for the acquisition (the "Acquisition") of up to an undivided 56% interest in 6 claim blocks comprising approximately 462,000 hectares located in the north-western section of Baja California, Mexico (the "Property"). The Optionors are an arm's length party to the Company, and therefore, shareholder approval of the Acquisition will not be required by the TSX Venture Exchange ("TSX-V").

Pursuant to the terms of the Option Agreement, the Company, through Minmay may incorporate a subsidiary pursuant to the laws of Mexico for the purpose of holding Minmay's respective interest in the Property. The Acquisition may occur in up to three phases. In phase one, the Company, through Minmay, will acquire a 25% interest in the Property by paying US$1,000,000 and issuing 500,000 common shares in the capital of the Company (the "Shares"). In phase two, Minmay may acquire an additional 25% interest in the Property (for an aggregate 50% interest) by spending not less than US$2,500,000 in expenditures on or before the 18 month anniversary of the date TSX-V approves the Acquisition (the "Effective Date"). In the final phase, Minmay may acquire a further 6% interest (for an aggregate 56% interest) in the Property by spending an additional US$1,500,000 in expenditures on or before the 30 month anniversary of the Effective Date. At any time after completion of phase one, the Company may elect not to acquire any further interest in the Property and immediately form a joint venture with the Optionors to further explore and develop the Property.

The Company has also entered into a Finder's Fee agreement dated July 9, 2010 with Mining Advisory Services Inc. The Company will pay a Finders' fees for the Acquisition in Shares within the maximum amount permitted by the policies of the TSX-V.

Closing of the Acquisition is subject, amongst other things, to the completion of satisfactory due diligence on the Property by the Company, including review of a title opinion, the preparation of a National Instrument 43-101 compliant technical report for the Property, financing and the approval of the TSX-V.

About Mayen Minerals Ltd.

Mayen is a Canadian junior exploration company focused on the acquisition, exploration, and development of precious and base metal deposits in Mexico. The Company is listed on the TSX Venture Exchange under the symbol MYM.

ON BEHALF OF THE BOARD

Dennis A. van Dyke, President, Chief Executive Officer and Director

FORWARD LOOKING STATEMENTS: This press release contains forward-looking statements. Forward-looking statements are statements that are not historical facts and are generally, but not always, identified by the words "expects", "plans", "anticipates", "believes", "intends", "estimates", "projects", "potential" and similar expressions, or that events or conditions "will", "would", "may", "could" or "should" occur. Although the Company believes the expectations expressed in such forward-looking statements are based on reasonable assumptions, such statements are not guarantees of future performance and actual results may differ materially from those in forward looking statements. Forward-looking statements are based on the beliefs, estimates and opinions of the Company's management on the date such statements were made. The Company expressly disclaims any intention or obligation to update or revise any forward-looking statements whether as a result of new information, future events or otherwise.

Neither TSX Venture Exchange nor its Regulations Services Provider (as that term is defined in policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release.

Contacts: Mayen Minerals Ltd. Dennis A. van Dyke President and Chief Executive Officer (604) 689-4733 www.mayenminerals.com