Castle Resources NI 43-101 Resource Estimate for Granduc Copper Project Exceeds Expectations

- Indicated resources are 3.75 million tonnes grading 1.59% Cu containing 131.4 million pounds of copper based on an 0.8% Cu cut-off grade

- Inferred resources are 15.8 million tonnes grading 1.36% containing 471.5 million pounds of copper based on an 0.8% Cu cut-off grade

- Exploration potential estimated to contain an additional 17 to 23 million tonnes grading between 1.3 to 1.6% Cu


TORONTO, ONTARIO--(Marketwire - Feb. 28, 2011) - Castle Resources Inc. (TSX VENTURE:CRI) ("Castle" or the "Company") is pleased to provide shareholders and investors with a new NI 43-101 resource estimate for the past producing Granduc Copper Mine near Stewart B.C.

Mike Sylvestre, President & COO, stated, "This initial resource estimate and the defined exploration potential conclusively demonstrates the exciting potential for the Granduc. Based on significant historical data and a limited 8,300 metre drill program completed in Castle's first drill program last year, we have begun the process of building a large high grade copper resource with excellent operating infrastructure already in place."

Mr. Sylvestre continued, "This exciting initial resource clearly justifies management's determination to aggressively drill the numerous exploration targets at the Granduc this year. Our primary focus now is to upgrade much of the initial resource from the inferred to the indicated category and grow the resource by drilling new zones down dip and along strike so as to expand the Granduc resource estimate later this year."

The mineral resource estimate was prepared by SRK Consulting (Canada) Inc. (SRK) of Vancouver B.C., an independent, international consulting practice that provides focused advice and solutions to clients, mainly from the earth and water resource industries.

Granduc Copper Project, Indicated Mineral Resource, Feb 28, 2011
Cut-off Quantity Cu Grade Contained Copper
(Cu %) (millions of tonnes) (Cu %) (millions of lbs)
0.5 4.04 1.52 % 135.7
0.8 3.75 1.59 % 131.4
1.0 3.35 1.67 % 123.2
1.2 2.75 1.79 % 108.7
1.4 2.12 1.94 % 90.8
 
Granduc Copper Project, Inferred Mineral Resource, Feb 28, 2011
Cut-off Quantity Cu Grade Contained Copper
(Cu %) (millions of tonnes) (Cu %) (millions of lbs)
0.5 17.7 1.28 % 500.8
0.8 15.8 1.36 % 471.5
1.0 13.1 1.45 % 418.6
1.2 9.2 1.59 % 323.1
1.4 5.9 1.76 % 228.4

SRK believes the Mineral Resource is most accurately represented at a 0.8% cut-off. Mineral resources that are not mineral reserves do not have demonstrated economic viability. All figures have been rounded to reflect the relative accuracy of the estimates. SRK is not aware of any environmental, permitting, legal, title, taxation, socio-political or marking issues that would materially affect the mineral resource. The resource estimate was completed under the supervision of independent Qualified Person Marek Nowak, P.Eng and Principle Geostatistician with SRK.

The resource estimate is based on a database containing approximately 2000 drillholes and 40,000 assays. Historical data was verified wherever possible against mine records including logs, sections and plans, however not all survey or assay data could be verified. Assays from the 2010 drillholes and re-sampling of historical core were used to further validate the data. All assays from the 2010 drilling were independently verified by SRK. SRK completed a site visit to the property in September 2010 during the Castle drill program but did not complete any independent sampling. SRK believes the data of sufficient quality for the definition of the mineral resource.

The Granduc copper deposit is a volcanogenic massive sulphide deposit ("VMS") with tabular, stratified mineralization zones which have been deformed by several phases of folding. SRK created grade shell models at a 0.7% cut-off for 13 domains, using historical sections and plans as a guide. Eleven of these domains lie within the Main Zone where historical mining took place and two zones were defined within the North Zone, approximately 1 km north of the Main Zone. All domains were modelled at a minimum width of 1.5 m. Mineralized domains at the extents of the deposits are open down-dip as well as along strike.

For the Main Zone, the blocks were estimate by ordinary kriging into blocks of 2 m by 10 m by 10 m. The North Zone was estimated using inverse distance squared methods into similar sized blocks. For volumetric accuracy, blocks were sub-blocked to 0.5m by 2.5m by 2.5m. Average bulk density values were applied to all blocks within the mineralized domains.

Estimated blocks were categorized into indicated and inferred classes based upon the density of drilling information available as well as overall confidence in the available data for domain interpretation. Blocks immediately below the lower limits of the underground mining where density of underground drilling was highest, were classed as indicated. Blocks further away from the mining levels where drillhole spacing was wider and there is less certainty in correlating between mineralized intercepts, was classed as inferred.

The mineral resources are limited to unmined areas based on a model of the historic mining limits. The historic mining limits were determined from mine closure records filed with the government in 1984. At this time SRK has not gained underground access and therefore cannot directly verify the boundary. SRK believes that this boundary has been conservatively defined on reliable records.

In addition to the mineral resources, SRK assessed the exploration potential defined by wider spaced drilling data. The exploration potential is based upon approximately 20 Main Zone and 13 North Zone drill holes that have been correlated with the resource domains, but are too widely spaced to define a resource. In the main zone, wide spaced drilling has intersect mineralized intervals down to the 325m (1065 ft) level and the exploration potential is largely defined by the down-dip extension of the mineralization from the inferred mineral resource. In the North Zone, the exploration potential has been defined by correlating widely space drillholes largely above the mineral resource. The resource is defined in an area where drilling density from an exploration drift was high enough to accurately quantify the resource. Fans of widely spaced surface and underground drillholes have been used to quantify the exploration potential.

The potential quantity and grade of the exploration potential is conceptual in nature and there has been insufficient exploration to define a mineral resource. It is uncertain if further exploration will result in the exploration targets being delineated as a mineral resource.

Total Exploration Potential
Estimated Quantity Range Estimated Grade Range
(millions of tonnes) (Cu %)
17 to 23 1.3 % to 1.6 %
Based upon a cut-off grade of 0.8 % Cu

Gold and silver grades were not estimated as the historical assay data for both commodities was unavailable. However, given that Newmont and Esso reported yearly gold and silver production figures during the life of mine, and Castle's recent drill results demonstrated gold and silver mineralization (see press release dated Dec 6, 2010), it suggests that future resource updates should include analysis of precious metals where supported by available data.

Granduc Highlights:

  • Newmont and Esso Minerals operated the Granduc Mine between 1971-1984; processed over 15 million tonnes of ore grading 1.71% Cu; produced 420 million pounds of copper (plus gold and silver credits); the mine was closed in 1984 due to low copper prices
  • Operators of the Granduc Mine invested over $115 million from Oct 1965 until start-up operations began in 1971
  • 17 km haulage tunnel remains in good condition today
  • Mining operations at the Granduc Mine consisted of crushing underground then processing of up to 9000 tpd. The concentrate was trucked on a 54 km all weather road to the year-round deep sea port facility in Stewart which remains in operation today
  • Bell Copper's exploration activities between 2004 and 2007 have confirmed mineralization within 4 kms to the north and south of the main Granduc orebody

Brad Leonard, P. Geo., Castle's Exploration Manager, is the Qualified Person responsible for the scientific and technical work (as defined under National Instrument 43-101) discussed in this press release, and has reviewed this press release.

About Castle Resources

Castle Resources Inc. is a Toronto-based junior mineral development company focusing on high-quality, advanced projects. Management's goal is to continue the redevelopment of the 100% owned past producing Granduc Copper Mine and begin new exploration activities; as well, management is quickly advancing the Elmtree Gold Project in New Brunswick toward feasibility in 2011. For more information please visit the Castle Resources' website at www.castleresources.com.

Disclaimer

Certain statements contained in this news release may contain forward-looking information within the meaning of Canadian securities laws. Such forward-looking information is identified by words such as "estimates", "intends", "expects", "believes", "may", "will" and include, without limitation, statements regarding the company's plan of business operations (including plans for progressing assets), estimates regarding mineral resources, projections regarding mineralization and projected expenditures. There can be no assurance that such statements will prove to be accurate; actual results and future events could differ materially from such statements. Factors that could cause actual results to differ materially include, among others, metal prices, risks inherent in the mining industry, financing risks, labour risks, uncertainty of mineral resource estimates, equipment and supply risks, title disputes, regulatory risks and environmental concerns. Most of these factors are outside the control of the company. Investors are cautioned not to put undue reliance on forward-looking information. Except as otherwise required by applicable securities statutes or regulation, the company expressly disclaims any intent or obligation to update publicly forward-looking information, whether as a result of new information, future events or otherwise.

This news release does not constitute an offer to sell or solicitation of an offer to sell any of the securities in the United States. The securities have not been and will not be registered under the United States Securities Act of 1933, as amended (the "U.S. Securities Act") or any state securities laws and may not be offered or sold within the United States or to a U.S. Person unless registered under the U.S. Securities Act and applicable state securities laws or an exemption from such registration is available.

Contact Information: Castle Resources Inc.
Mike Sylvestre
President & Chief Operating Officer
416-366-4100
mike@castleresources.com
or
Castle Resources Inc.
Lenny Foreht
VP Corporate Development
416-364-2266
lforeht@hotmail.com