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Castle Resources Encounters Significant Copper Mineralization at Granduc Project

Castle Resources Inc. (TSX VENTURE:CRI) has updated investors regarding its Granduc Project and provide the balance of drill results from the recently completed 8,300 metre, 18 hole drill program at the Granduc Copper Project near Stewart, B.C.

"Drill results to date have confirmed there is significant copper mineralization at Granduc," commented Mr. Mike Sylvestre, President and COO of Castle Resources. "Intersections show a strong pattern of increasing copper grade and lens thickness in both downdip and southwest directions, demonstrating the potential for a much larger copper zone than the Company initially anticipated."

The objective of Castle's 2010 drill program at Granduc was to test the down dip extent of the historical deposit as well as replicate certain Newmont and Esso drill results. This goal was achieved as all holes have encountered visible copper mineralization along a 1,000 metre strike. These initial results indicate that the historical in-situ Newmont and Esso resource estimates appear to be reliable; the larger objective is to continue this process and target the balance of the downdip mineralization and extend the strike to the south through a comprehensive drill campaign next field season.

The development strategy at Granduc is now focused on generating a NI 43-101 resource estimate based on this year's drilling as well as historic drilling and then moving quickly to commission a Preliminary Economic Assessment. In tandem, management is preparing a detailed exploration and mine rehabilitation plan that will focus on the balance of targets not yet drilled downdip and along strike. This will entail the partial rehabilitation of the 17 km long tunnel connecting the Granduc underground workings with the former millsite and parts of the mine infrastructure, including ramps and exploration drifts originally developed by Newmont and Esso. This development strategy is already underway and will be implemented starting in the spring of 2011.

Based on this year's successful drill results targeting the downdip extent of the historic Granduc orebody, management is now focusing on the potential for additional strike length to the south. Bell Copper, the previous owners of the Granduc Project, tested the along-strike continuity of the known mineralization to the south of the mine workings in 2005 and 2006 and demonstrated that the 'South Zone' was likely an extension of geophysical anomalies with the historic mine. Given the proximity of several of this year's drill holes to Bell's drilling, management aims to further test the 'South Zone' next field season.

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

Independent Quality Control and Analytical Protocol

Castle Resources implemented a QA/QC protocol for all its exploration and diamond drilling program on the Granduc. The drilling contractor was Morecore Drilling Services and core diameter was a combination of NQ and thin wall NQ, enabling the possibility for at least two step-downs if ground conditions should require it. All drill hole locations were spotted using a hand-held Garmin GPS receiver with a 2m to 6m accuracy. Core was delivered to the secure Core Shack facility located on the property. In addition to recovery and RQD (Rock Quality Designation) data, geologic parameters including lithology, alteration, presence and identification of sulphide mineralization along with other geologic parameters are noted and recorded. Core was marked in one meter intervals for splitting, sampling and assaying, unless geologic data indicate a shorter sample interval. Prior to splitting, all core was photographed. Core splitting was done with a diamond core saw or by manual splitter and ½ of the drill core was submitted to EcoTech Laboratories (part of the Stewart Group of Companies), a certified sample preparation facility located in Stewart B.C., where samples were crushed, pulped and screened to 100 mesh. The pulps were then sent by courier to the main EcoTech laboratory facility in Kamloops B.C. for assay, while the rejects are stored at the EcoTech prep facility in Stewart. All samples were analysed through an aqua-regia digest and analysesd through a 35 element ICP/MS package and gold fire assay with an Atomic Absorption (AA) finish. All sample over-runs through the ICP package automatically were fire assayed with an AA finish.

A QA/QC protocol was followed for the drill core sampling program, which involved inserting sample blanks and standards at regular intervals into the sample stream. Blanks were inserted at the nominal rate of 1 in every 35th sample as well as after a sample which contained significant visible sulphides. Sample standards were inserted at the nominal rate of 1 in every 20th sample (alternating between OREAS_93 and OREAS_95). Every 20th sample on odd multiples was selected as a "referee sample" whereby instructions were given to the prep facility to prepare 2 pulps, analyze one and keep the second to be sent to another credited laboratory for verification of results. Three duplicate samples were selected per hole, located in a mineralized zone to assure continuity of higher grade results, where half the core was quartered and sent as a separate sample. Sample tags made of sturdy Tyvek were inserted into each plastic sample bag and securely sealed. The sample number along with the sample interval was recorded on the drill log. The sample interval was recorded in the sample tag book. A 3rd sample tag was stapled into the core box at the end of the sample interval. All core is currently and securely stored in the remote camp location.

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.

Source: Castle Resources Inc.


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