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STRICTLY PRIVATE AND CONFIDENTIAL
 
June 18, 2008
 
To:
 
Mexoro Minerals Ltd.
C. General Retana #706
Col. San Felipe
Chihuahua, Mexico  CP 31203

 
Attention : Mario Ayub, Chief Executive Officer
 

Dear Mr. Ayub:
 
Re:
Amendment to Letter of Intent dated May 2, 2008 (the “Letter of Intent”) between
Mexoro Minerals Ltd. (“Mexoro”) and Paramount Gold and Silver Corp.
(“Paramount”) with respect to the Proposed Strategic Alliance (the “Proposed
Transaction”) between Mexoro and Paramount

 
This amendment (the “Amendment”) to the Letter of Intent is further to the
discussions to date between Mexoro and Paramount.  The provisions of this
Amendment, together with the Letter of Intent, will confirm the present interest
of the parties with respect to the Proposed Transaction.
 
Capitalized terms used but not defined herein shall have the meaning ascribed
thereto in the Letter of Intent.
 
The undersigned agree to amend the Letter of Intent as follows:

1.           Extension of Term. The parties agree to extend the date, prior to
which the minimum amount of eight (8) million Units in the capital of Mexoro
(the “Minimum Investment”) must be subscribed for by Paramount, from June 23,
2008 to July 21, 2008. As a result, the parties further agree that the
references to June 23, 2008 under the headings “Private Placement”, “Convertible
Debenture”, “Closing and Conditions of Closing”, “No Negotiations with Other
Parties” and “Termination” in the Letter of Intent are hereby extended to July
21, 2008.
 
 
 
 

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2.           Convertible Debenture. The parties agree that Mexoro may defer all
interest payments on the secured convertible debenture dated May 9, 2008 in the
aggregate principal amount of $500,000 (the “May Debenture”), issued pursuant to
the Letter of Intent, until the date of the Minimum Investment by Paramount
without penalty or default, provided that (i) all such accrued interest shall
become immediately payable upon the date of the Minimum Investment, and (ii) in
the event that the Letter of Intent, as amended, is terminated, all accrued
interest will become immediately payable to Paramount. The parties further agree
that Paramount shall loan the additional sum of US$370,000 to Mexoro on or
before June 21, 2008 to be secured by a one year convertible debenture (the
“June Debenture”) bearing interest at 8% and to be secured by all of the assets
of Mexoro and its subsidiaries including Sunburst Mining de Mexico S.A. de C.V.
Paramount shall have the right to convert the aggregate principal amount of
$370,000 of the June Debenture to 740,000 Units of Mexoro on the same terms and
conditions as the May Debenture. Paramount agrees that payment of interest on
the June Debenture shall be deferred until July 21, 2008, provided that (i) all
such accrued interest shall become immediately payable on July 21, 2008, and
(ii) in the event that the Letter of Intent, as amended, is terminated, all
accrued interest will become immediately payable to Paramount.

3.           Registration Rights. The parties agree that Mexoro will use its
best efforts to file and have declared effective a registration statement with
the Securities and Exchange Commission pursuant to the Securities Act of 1933,
with respect to all shares of common stock of Mexoro issued and issuable to
Paramount pursuant to the May Debenture, the June Debenture and the private
placement of Units pursuant to the Letter of Intent, as amended, within six (6)
months of the date of the Minimum Investment, all subject to the terms and
conditions of a registration rights agreement, in a form satisfactory to
Paramount, to be entered into with Paramount on the date of the Minimum
Investment.

4.           Future Financings. Paramount will be provided a  right of first
refusal for a period of 4 years from the date hereof on all future financings of
Mexoro whether by way of loan or share subscription subject to 14 days written
notice by Mexoro to Paramount with 90 days to close save and except for the
current debt restructuring which includes the settlement of $1.5 million of debt
by way of issuance of equity units priced at $0.50 USD per unit.  Each unit
comprised of 1 share plus 1/2 common share purchase warrant.  One full warrant
is exerciseable at $0.75.  This right of first refusal is only provided if
Paramount meets the minimum subscription of 8 million Units ($4 million).  In
the event that Paramount agrees to additional financing and fails to complete in
the 90 day time period, then Paramount shall forfeit its right of first refusal
on any subsequent financing.
 

Except as amended to reflect the above, the Letter of Intent remains in full
force and effect in accordance with its terms.
 
The parties acknowledge and agree that this Amendment is subject to review and
approval by the Board of Directors of Paramount.
 
This Amendment may be executed in any number of counterparts, all of which taken
together will be deemed to constitute one and the same instrument. This
Amendment may be signed and delivered by facsimile and same shall constitute
effective execution of the document.
 
 
 
 

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To confirm this Amendment, please sign the enclosed duplicate copy where
indicated below and return it to Paramount within three (3) business days of the
date of receipt, or at that time the proposal set out above will expire
automatically.
 
Yours very truly,
 
PARAMOUNT GOLD AND SILVER CORP.
 

 
Per:                                                                           
Christopher Crupi
President and CEO

Phone:  613-226-9881   346 Waverley Street, Ottawa, Ontario Canada  K2P
0W5   Fax:  613-226-5106
 
 
 

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* * * * *
 
This Amendment, together with the Letter of Intent, reflects accurately the
parties’ understanding and agreement with respect to the matters set out above.
 

 
MEXORO MINERALS
LTD.                                                                                                SUNBURST
DE MEXICO S.A. DE C.V.
 

 
Per:                                                                                          Per:                                                               
         
Steven A. Sanders, Director                                   Steven A. Sanders,
Assistant Secretary

 

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