Cornerstone Signs Definitive Agreement to Purchase Lone Mountain and Other U.S. Properties from Copper One

Cornerstone Metals Inc. (TSX VENTURE:CCC) ("Cornerstone" or the "Company")
Further to its news releases of March 21st and May 14th 2013, it is pleased to
announce that it has entered into the definitive agreement ("the Agreement")
with Copper One Inc. to acquire all of the shares of Copper One's U.S.
subsidiary, Copper One USA Inc. ("Copper One USA"), which holds 6 properties
located in Southwest United States, with the principal property being Lone
Mountain, New Mexico.


The other properties are West Jerome; Teague Springs; West Safford and Twin
Peaks in Arizona and Mimbres in New Mexico. 


Under the terms of the Agreement, Copper One will receive 2,250,000 Cornerstone
common shares on the closing date of the sale, plus the following additional
consideration tied to specific properties:




--  Within 30 days of completing a feasibility study in respect of the Lone
    Mountain property, Cornerstone will (a) issue to Copper One 2,000,000
    Cornerstone common shares; (b) pay to Copper One $1,000,000 in cash or
    shares at Copper One's option; and (c) grant to Copper One a 0.5% net
    smelter return royalty capped at $5,000,000, which may be repurchased by
    Cornerstone for $1,000,000 in cash or shares at Copper One's option at
    any time up until the earlier of eight years following the date of the
    Agreement and the date on which commercial production is achieved in
    respect of the Lone Mountain property. 

--  Within 30 days of completing a feasibility study in respect of the West
    Jerome property, Cornerstone will: (a) issue to Copper One 500,000
    Cornerstone common shares; (b) pay to Copper One $750,000 in cash or
    shares at Copper One's option; and (c) grant to Copper One a 0.5% net
    smelter return royalty capped at $4,000,000, which may be repurchased by
    Cornerstone for $800,000 in cash or shares at Copper One's option at any
    time up until the earlier of eight years following the date of the
    Agreement and the date on which commercial production is achieved in
    respect of the West Jerome property. 

--  Within 30 days of completing a feasibility study in respect of any of
    the other properties, Cornerstone will: (a) issue to Copper One 350,000
    Cornerstone common shares; (b) pay to Copper One $375,000 in cash or
    shares at Copper One's option; and (c) grant to Copper One a 0.5% net
    smelter return royalty capped at $3,000,000, which may be repurchased by
    Cornerstone for $350,000 in cash or shares at Copper One's option at any
    time up until the earlier of eight years following the date of the
    Agreement and the date on which commercial production is achieved in
    respect of such property.  



750,000 of the 2,250,000 Cornerstone shares issued to Copper One on the closing
date of the sale will be subject to a voluntary 12-month hold period. 


The Agreement remains subject to certain customary closing conditions. 

Courtney Shearer, interim-CEO remarked, "We will now have a predominantly
copper-focused company. The geographic and strategic clustering of the
properties will provide technical and logistical efficiencies to explore and
develop these projects."


About Cornerstone Metals

Cornerstone's objective is to advance exploration / development stage copper and
precious metals properties to production in the Americas. The Company's
Management and Board core competence is in exploration, permitting, development,
construction, and operation of mining projects.


On Behalf of Cornerstone Metals Inc.

Courtney Shearer, interim-CEO and President

For more information about Cornerstone Metals Inc., please visit:
www.cornerstonemetals.ca


FORWARD LOOKING STATEMENTS: This document includes forward-looking statements as
well as historical information. Forward-looking statements include, but are not
limited to, statements with respect to the Company's exploration and development
prospects. When used in this document, the words "anticipate", "believe",
"estimate", "expect", "intent", "may", "project", "plan", "should" and similar
expressions may identify forward-looking statements. Although Cornerstone Metals
Inc. believes that its expectations reflected in these forward looking
statements are reasonable, such statements involve risks and uncertainties and
no assurance can be given that actual results will be consistent with these
forward-looking statement. Important factors that could cause actual results to
differ from these forward-looking statements include the potential that
fluctuations in the marketplace for the sale of minerals, the inability to
implement corporate strategies, the ability to obtain financing and other risks
disclosed in the Company's filings made with Canadian Securities Regulators. The
Company does not undertake to update any forward-looking statements, except in
accordance with applicable securities laws.


NEITHER THE TSX VENTURE EXCHANGE NOR ITS REGULATION SERVICES PROVIDER (AS THAT
TERM IS DEFINED IN THE POLICIES OF THE TSX VENTURE EXCHANGE) ACCEPTS
RESPONSIBILITY FOR THE ADEQUACY OR ACCURACY OF THIS RELEASE.


FOR FURTHER INFORMATION PLEASE CONTACT: 
Cornerstone Metals Inc.
Courtney Shearer
Interim-CEO and President
[phone]
[e-mail]
www.cornerstonemetals.ca