Sheffield Resources Ltd.
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Sheffield Resources Ltd.

August 24, 2007 14:13 ET

Sheffield Reports 3.71% Copper Over 37.8 Metres

VANCOUVER, BRITISH COLUMBIA--(Marketwire - Aug. 24, 2007) - Sheffield Resources Ltd. ("Sheffield") (TSX VENTURE:SLD)(FRANKFURT:S2Q) is pleased to announce additional assay results from the ongoing diamond drill program focused on the Engels Mine copper prospect at the Moonlight Copper Project located in Plumas County, California.



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DRILL HOLE COPPER (%) LENGTH (metres) FROM (metres) TO (metres)
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07-E-4 3.71% 37.8 (124.0 feet) 0.0 37.8
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Initial assay results for hole 07-E-4 continues the series of high-grade copper intersections by "HQ" gauge core holes 07-E-1 to 07-E-3. Hole 07-E-4 was drilled at minus sixty degrees from the same drill site as core hole 07-E-3, which was drilled at minus forty-five degrees. Hole 07-E-4 averages 3.71% copper from the surface to a total depth down the hole of 37.8 metres. This hole contains a number of higher grade intercepts including a 22 metre long section from 10m to 32m that averaged 6.01% copper, the details of which are presented below:



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DRILL HOLE COPPER (%) LENGTH (metres) FROM (metres) TO (metres)
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07-E-4 3.71% 37.8 0.0 37.8
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Including
interval 6.01% 22.0 10.0 32.0
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Which also
includes 17.95% 2.0 16.0 18.0
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and 7.81% 2.0 18.0 20.0
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and 3.65% 2.0 20.0 22.0
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and 15.7% 2.0 22.0 24.0
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and 8.47% 2.0 24.0 26.0
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and 7.26% 2.0 26.0 28.0
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Hole 07-E-4 was terminated at 37.8 metres in depth due to drilling difficulties. The core recovered between 30m to 37.8m of depth was logged as backfill and mineralized rock fragments which on assay were found to contain between 0.37% copper and 1.23% copper over 2m sample intervals.

Gold and silver assays for holes 07-E-1 to 07-E-3 are reported below. The highest silver assay reported for the first three holes was 220 g/t and the highest gold content reported was 2.04 g/t. Gold and silver assays for hole 07-E-4 will be reported at a future date when complete precious metal assays for the hole are in hand.



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COPPER GOLD SILVER LENGTH FROM TO
DRILL HOLE (%) (g/t) (g/t) (metres) (metres) (metres)
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07-E-1 2.95% 0.14 23.6 54 (177.2 feet) 0.0 54.0
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07-E-2 2.54% 0.05 22.1 44 (144.4 feet) 0.0 44.0
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07-E-3 2.99% 0.09 27.9 28 (91.9 feet) 0.0 28.0
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Drilling continues at the Engels Mine area of the Moonlight Project where hole 07-E-8 is in progress. All holes drilled in the ongoing diamond drill program are HQ gauge.

The drill holes reported herein are the first modern drill holes from the Engels Mine area which is one of four principal target areas on the Moonlight Copper/Silver Project. A preliminary 43-101 compliant resource was reported in March 2007 for the adjacent Moonlight Deposit which remains open to resource expansion laterally and to depth.

Quality Control and Assurance

A rigorous Quality Control and Assurance program (QC/QA) is in place, including systematic inclusion of standard sample materials, blank samples, duplicate samples and inter-laboratory check assaying. Samples are sent in sealed containers to ALS Chemex in Reno, Nevada. ALS Chemex is a recognized ISO 9000 registered laboratory. The control samples and duplicate assay results received for the drilling program demonstrated to Sheffield Resources that the assay results reported herein are reliable.

The exploration program is managed by Robert Wetzel, a California registered professional geologist and qualified person. David M Jenkins, P.Geo., and president of Sheffield Resources is designated the qualified person for the Moonlight Copper Project.

About Sheffield Resources Ltd.

Sheffield Resources Ltd. is an exploration and development company focused on the acquisition and systematic development of copper and nickel/cobalt deposits with potential for large tonnages of ore that are located close to infrastructure in politically stable areas.

This news release may contain forward-looking statements including but not limited to comments regarding the timing and content of upcoming work programs, geological interpretations, receipt of property titles, potential mineral recovery processes etc. Forward-looking statements address future events and conditions and therefore involve inherent risks and uncertainties. Actual results may differ materially from those currently anticipated in such statements. Sheffield Resources Ltd. relies upon litigation protection for forward-looking statements.

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