Callinan Winter Exploration Update

April 7, 2005

The Company’s exploration program on their Thompson Nickel Belt claims has been suspended temporarily.

A total of eight drill holes have been completed, four each on the Pine Claim and the Phillips Lake claim. Ground and down hole geophysics were able to locate sizeable zones of conductivity on both properties. Drill testing of the down hole EM target on the Pine claim intersected long sections of sulphide mineralization. The hole designed to test the target on the Phillips Lake claim did not reach the target depth. Difficult ground conditions and the onset of “breakup” forced the company to end the hole before the desired target was intersected. The company is intent on drill testing this conductor, and plan to drill it from land as part of its summer exploration program.

The core is currently being split, sampled and shipped to Acme Analytical Laboratory in Vancouver where it will be analyzed for nickel, copper gold and sliver as well as platinum group metals. The results will be reported as soon as they are received.

Previous exploration on the Pine claim included intercepts of as much 2.93% Ni as well as 0.43% Ni and 0.05 oz/t Au over 18 ft of pyrite and pyrrhotite.

Callinan’s diamond drill hole CAS-4 on the Pine property, designed to test a conductive target defined by down hole geophysics, intercepted more than 215 ft of mineralization including sections of solid pyrrhotite and pyrite with visible chalcopyrite.

This winter, the nickel belt has seen a flurry of exploration as strong demand for nickel has continued to push the price of the metal to new highs. According to their 2004 annual report, Inco ltd. is experiencing a sustained trend of lower mine production from their Thompson operations resulting in reliance on purchased nickel intermediates from as far away as Australia to maintain their smelting concern. They are currently searching for a cost effective alternative.

The company’s Pine and Phillips Lake properties are located approximately 110 and 60 kms from Thompson, respectively, close to a paved road and a railway.

Abnormal climates and waist deep snow fall this year in the north of Manitoba resulted in a lack of freezing of swampy ground that rendered mobilization to Callinan’s Fox River and Cal properties impossible. The Company remains optimistic about the potential of the properties. Ground geophysics have defined strong conductors in potentially favourable hosts, which the company plans to drill test as soon as conditions permit.

On Behalf of the Board ,

CALLINAN MINES LTD.

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