Cornerstone Amends LOI on SW US Copper Projects

Cornerstone Metals Inc. (TSX VENTURE:CCC) ("Cornerstone" or the "Company")
announces that further to its news release of March 21, 2013, it has signed
amendments to its letter of intent ("LOI") to acquire all of the shares of
Copper One USA, Inc., pursuant to which:




--  the Company agreed to issue to the vendor an additional 750,000 shares
    on closing in recognition of the existing financial assurances that are
    in place (totalling approximately US$250,000); and 

--  the date for paying the US$55,000 Lone Mountain property payment was
    extended from April 1, 2013 to May 15, 2013. The Company has made this
    payment.



The SW US copper projects are comprised of six separate properties in New Mexico
and Arizona with the principal property being the Lone Mountain project in New
Mexico. 


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 & President

Forward-looking information

All statements included in this press release that address activities, events or
developments that the Company expects, believes or anticipates will or may occur
in the future are forward-looking statements. These forward-looking statements
involve numerous assumptions made by the Company based on its experience,
perception of historical trends, current conditions, expected future
developments and other factors it believes are appropriate in the circumstances.
In addition, these statements involve substantial known and unknown risks and
uncertainties that contribute to the possibility that the predictions,
forecasts, projections and other forward-looking statements will prove
inaccurate, certain of which are beyond the Company's control. There can be no
assurance that any forward-looking 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. Except as required by law, Cornerstone doe snot
intend to revise or update these forward-looking statements after the date
hereof or to revise them to reflect the occurrence of future unanticipated
events.


FOR FURTHER INFORMATION PLEASE CONTACT: 
Cornerstone Metals Inc.
Courtney Shearer
403-804-8636
888-255-9604 (FAX)
[e-mail]