Summo hits extension of Centennial copper deposit

A 15-hole exploration program targeting the southern end of the Centennial copper oxide deposit in southeastern Utah has uncovered a new mineralized zone for Denver-based Summo Minerals (SMA-T).

Covering a 1,200-by-800-ft. area adjacent to the proposed Centennial pit, 14 of the 15 holes intersected the newly discovered zone over an average thickness of 44 ft. with an average grade of 0.504% copper. Highlights from the program include:

– hole 1, which hit 40 ft. averaging 0.53% copper;

– hole 6, which intersected 40 ft. of 0.43% copper;

– hole 9, which cut 125 ft. of 0.26% copper;

– hole 10, which cut 70 ft. of 0.53% copper;

– hole 12, which hit 70 ft. averaging 0.47% copper;

– hole 14, which returned 30 ft. grading 1.12% copper; and

– hole 15, which hit 40 ft. of 0.86% copper.

The zone lies 250 ft. below the surface, in the Dakota sandstone unit and the underlying Burro Canyon Formation sandstone unit. The mineralization consists of fine-grained chalcocite and bornite and remains open to the southeast. Initial cyanide leach tests on the new intercepts returned an average recovery rate of greater than 90%.

Based on the encouraging results, Summo will carry out a 50-hole drill program to infill the most recent holes and to test for mineralized extensions of the zone to the southeast.

The Centennial is the largest of three copper oxide deposits outlined on the Lisbon Valley property in San Juan Cty. Lisbon Valley is already fully permitted for an open-pit, heap-leach operation designed to produce 40 million lbs. cathode copper annually at a cash operating cost of US48 per lb.

The property is at the southeastern end of the faulted Lisbon salt anticline. The Lisbon Valley Fault is a major axial structure, which exhibits up to 4,000 ft. of displacement and, outward from the fault, as much as 1,500 ft. along favourable sandstone beds. The deposit has at least 46.5 million tons of reserves grading 0.43% copper with a 2.36-to-1 stripping ratio, and is still open to expansion.

Lisbon Valley, which is undergoing a feasibility study, was permitted in 1997 but had to fight off an environmental challenge, which the company defeated in 1999. Two years earlier, a US$45-million project loan had been approved, but this commitment expired while the company was fighting off the challenge by environmentalists.

Resource Capital Fund holds an approximate 31.4% interest in Summo; St. Mary Minerals owns 19.25%.