Orosur Mining : US$250,000 Financing at 102% Premium to Market

Orosur Mining Inc. - US$250,000 Financing at 102% Premium to Market

Medellín, Colombia, July 10, 2018. Orosur Mining Inc. ("Orosur" or the "Company") (TSX/AIM: OMI) is delighted to announce that it continues to advance discussions to finance the next stage of exploration at the Anzá project in Colombia. In connection with these discussions, a sophisticated international mining company (the "Subscriber") has agreed to advance US$250,000 to subscribe for 3,603,077* common shares of Orosur at a price of CAD$0.091 (GBP 0.052*) per share (the "Subscription"). The share price represents a 102% premium to the closing price of the Company's common shares on the Toronto Stock Exchange (the "TSX") on July 9, 2018.

Completion of the Subscription is subject to, amongst other things, the execution of definitive private placement documentation and the approval of the TSX and admission of the common shares to trading on AIM ("Admission").

Upon Admission, the total number of common shares and voting rights issued and outstanding will be 121,189,982 and the total number of options and warrants outstanding shall remain unchanged at 17,241,010. The common shares issued in connection with the Subscription will be subject to a hold period expiring four months and one day following the closing date in accordance with applicable Canadian securities laws. The Company expects to close the Subscription during August 2018. At closing, it is anticipated that the Subscriber will own approximately 2.97% of the Company's issued and outstanding common shares on an undiluted basis.

The net proceeds from the Subscription will be used for general corporate purposes and working capital requirements.

About Orosur Mining Inc.

Orosur Mining Inc. (TSX: OMI; AIM: OMI) is a fully integrated gold producer, developer and explorer focused on identifying and advancing gold projects in South America. The Company operates the only producing gold mine in Uruguay (San Gregorio) and has assembled an exploration portfolio of high quality assets in Uruguay, Chile and Colombia.

*CAD exchange rate as at July 9th, 2018 (CAD$1.00:0.576GBP & CAD$1.31:US$1.00)

For further information, please contact:

Orosur Mining Inc

Ignacio Salazar, Chief Executive Officer Ryan Cohen, VP Corporate [e-mail]

Tel: [phone]

Cantor Fitzgerald Europe - Nomad & Joint Broker David Porter/Keith Dowsing

Tel: [phone]

Numis Securities Limited - Joint Broker John Prior / James Black / Paul Gillam Tel: [phone]

The information contained within this announcement is deemed by the Company to constitute inside information as stipulated under the Market Abuse Regulation ("MAR"). Upon the publication of this announcement via Regulatory Information Service, this inside information is now considered to be in the public domain. If you have any queries on this, then please contact Ryan Cohen, VP Corporate Development of theCompany (responsible for arranging release of this announcement on behalf of the Company) on: [phone].

Forward Looking Statements

All statements, other than statements of historical fact, contained in this news release constitute "forward-looking statements" within the meaning of applicable securities laws, including but not limited to the "safe harbour" provisions of the United States Private Securities Litigation Reform Act of 1995 and are based on expectations estimates and projections as of the date of this news release. Forward-looking statements include, without limitation the expected completion of a US$250,000 Subscription for common shares, the negotiation and execution of definitive agreements; the ability to advance the Anzá property, the approval of the TSX and other approvals. There can be no assurance that such statements will prove to be accurate. Such statements are subject to significant risks and uncertainties, and actual results and future events could differ materially from those anticipated in such statements. The Company disclaims any intention or obligation to update or revise any forward-looking statements whether as a result of new information, future events and such forward-looking statements, except to the extent required by applicable law.

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