Sierra Minerals Appoints Chief Financial Officer

TORONTO, ONTARIO, Aug 05 (MARKET WIRE) --
Sierra Minerals Inc. (TSX: SIM) ("Sierra" or the "Company") is pleased to
announce the appointment of Ms. Rebecca Hudson as Chief Financial Officer
of the Company. Ms. Hudson will be based at the Company's head office in
Toronto.

Ms. Hudson was most recently Controller of Zacoro Metals Corp.
("Zacoro"). Zacoro is a widely held Toronto-based mining company, with
exploration and development projects in Mexico. In addition to assuming
responsibility for financial reporting and internal controls, Ms. Hudson
managed all local Mexican financial, tax and legal matters working
through Mexican accounting and law firms. Prior to this, Ms. Hudson spent
two years with Xstrata Canada (formerly Falconbridge Limited), as
Manager, Financial Reporting and Control. She played a key role in the
implementation of Sarbanes-Oxley regulations. Ms. Hudson has also
recently provided consulting services to IAMGOLD Corporation and Argenta
Oil and Gas.

Ms. Hudson holds a Bachelor of Arts with a concentration in accounting
and a Masters of Accounting with a concentration in taxation from the
University of Waterloo. She earned her C.A. designation in 2000 with
Grant Thornton LP, followed by two years with PricewaterhouseCoopers LLP
in the Dominican Republic. Ms. Hudson is fluent in both English and
Spanish.

"We are extremely pleased to welcome Rebecca to the new Sierra team. I
believe that her strengths in financial reporting and control coupled
with her background in mining, specific knowledge of operating in Mexico
and the ability to work seamlessly in both English and Spanish, will be
invaluable as we strengthen our financial controls and grow the Company,"
stated Michael Farrant, President and CEO of Sierra. "The addition of
Rebecca rounds out our new management team following the recent
announcement of Phil Davies as Chief Operating Officer (see press release
dated July 9, 2008). I am confident that we now have the people in place
to execute our plans and look forward to working with them both."

New Head Office Address

The Company also wishes to announce that it has moved its Toronto head
office as follows:

SIERRA MINERALS INC.
8 King Street East, Suite 810
Toronto, ON M5C 1B5
Tel: (416) 366-8211
Fax: (416) 366-7596

About Sierra Minerals

Sierra Minerals Inc. (TSX: SIM) is a Canadian based gold production and
exploration company. Through its Mexican subsidiary, it owns 100% of the
Cerro Colorado Gold Mine in Sonora, Mexico. The Company is currently
completing its initial NI 43-101 mineral resource estimate on the
property and plans to increase annualized production from 20,000 to
30,000 ounces of gold. In addition, the Company is exploring its
extensive regional land package in Mexico which covers over 30,000
hectares. Further information about Sierra Minerals and the Cerro
Colorado Gold Mine can be found on the Company's website at
www.sierraminerals.ca.

FORWARD-LOOKING STATEMENTS

This news release includes "forward-looking information", as such term is
defined in applicable securities laws. The forward-looking information
includes, without limitation, the success of exploration activities and
other similar statements concerning anticipated future events, conditions
or results that are not historical facts including the extent of future
production from the Cerro Colorado Gold Mine. These statements reflect
management's current estimates, beliefs, intentions and expectations;
they are not guarantees of future performance. The Company cautions that
all forward looking information is inherently uncertain and that actual
performance may be affected by a number of material factors, many of
which are beyond the Company's control. Such factors include, among
others, risks and uncertainties relating to exploration and development;
the ability of the Company to obtain additional financing; the Company's
limited operating history; the need to comply with environmental and
governmental regulations; political and economic instability and general
civil unrest in Mexico, if any; potential defects in title to the
Company's properties; fluctuations in currency exchange rates;
fluctuating prices of commodities; operating hazards and risks;
competition; and other risks and uncertainties, including those described
in the Company's other regulatory filings filed with the Canadian
Securities Administrators and available at www.sedar.com. Accordingly,
actual future events, conditions and results may differ materially from
the estimates, beliefs, intentions and expectations expressed or implied
in the forward-looking information. All statements are made as of the
date of this news release and the Company is under no obligation to
update or alter any forward-looking information.

Contacts:
Sierra Minerals Inc.
Michael Farrant
President and CEO
(416) 278-4149
(416) 366-7596 (FAX)
Email: info@sierraminerals.ca
Website: www.sierraminerals.ca

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