Callinan Mines Limited

Callinan Mines Limited

April 27, 2007 11:22 ET

Callinan Mines Provides Exploration Update

VANCOUVER, BRITISH COLUMBIA--(CCNMatthews - April 27, 2007) - Callinan Mines (TSX VENTURE:CAA) is pleased to provide an update on the status of its Manitoba exploration undertakings.

Fox River

Callinan's continuing joint venture drill program with Bell Resources in the Fox River camp has so far drill tested 7 separate conductive targets. Mafic and ultramafic intrusions bearing metallic sulphide mineralization were intersected as part of the program in varying widths.

On grid 07-5, the company has intercepted a greater than 30 meter width of 70% massive sulphides. The sulphides are fine grained. It is not known whether the sulphide pentlandite is present, but pyrite and pyrrhotite are both present. The zone of massive sulphides is more than 30 meters in core length.

Field geologist Vic Sidic described the samples at the Fox River site as, "Very fine in consistency, exhibiting sulphide structures that have likely been re-constituted since their formation." Graphite mineralization is also present in some of the targets tested. The core has been logged and split in half and has been sent to Acme Labs of Vancouver for assay.

President Muzylowski is cautiously optimistic about the results to date. "The ultra-mafic rocks that we have intersected have me assured that we're hunting in the right area. The mineral content of the massive sulphide intercepts will ultimately be determined by the assay results."

Approximately one third of the prioritized conductors on the joint venture's 200,000+ hectare Fox River property have been tested as part of this program. Once the melting snow has drained from the area, the company intends to continue diamond drilling in its hunt for nickel sulphides, until all prospective targets have been sampled.

In its next phase, the Fox River exploration program will take advantage of the thawing of the surface area to carry out a geochemical program and will further prioritize the conductors located by airborne survey.

Snow Lake Cal Claims

Callinan will soon commence drilling on the Cal Claims in the Snow Lake area of Manitoba. Previous claim holders have located a zone of mineralization approximately 100 ft. thick. Not all assays were filed by the previous operator. Those available indicate up to 0.9% nickel and up to 3.78% copper in a peridotite host. (source: Manitoba government assessment files).

"The mineralization at the Cal Claims has become more important in the context of today's metal prices," Mike Muzylowski explained. "The zone is open at depth and on strike, and the mineralization is shallow. The dip of the mineralized zone is nearly flat."

This drilling is designed to confirm the grades and to carry out a metallurgical study on the mineralization. The company will also assay for platinum, palladium and cobalt. Platinum group metals are associated with the massive sulphide phyrrotite, and are sometimes present in sulphides that carry nickel values.

The Cal program will likely last 2 - 3 weeks and consists of approx 1,500 m of drilling. Magnetic anomalies indicating an extension of the existing mineralization to an area 432m by 366m will be tested.

Upon completion of drilling, the drill crews and equipment will be moved to Fox River so that two drill rigs can continue the intensive campaign in that area.

All projects are under the supervision of Pat DeVeaux, a qualified person as defined by NI 43-101 who has reviewed and approved the technical information in this release.

The TSX Venture Exchange has not reviewed, and is not responsible for the adequacy or accuracy of this release.

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