Summo confirms grades at Johnson

Junior Summo Minerals (SMA-T) reports that exploration drilling at the dormant Johnson Camp mine in Arizona has confirmed the thickness and grade of the Copper Chief deposit.

Results from eight infill holes are as follows:

• Hole 1 intersected 180 ft. grading 0.69% total copper (0.59% being in the form of acid-soluble copper);
• Hole 2 cut 140 ft. of 0.31% copper (0.26% acid-soluble);
• Hole 3 returned 80 ft. of 0.48% copper (0.44% acid-soluble);
• Hole 4 hit 270 ft. of 0.24% copper (0.22% acid-soluble);
• Hole 5 intersected 190 ft. of 0.33% copper (0.31% acid-soluble);
• Hole 6 cut 160 ft. of 0.32% copper (0.27% acid-soluble);
• Hole 7 returned 170 ft. of 0.38% copper (0.35% acid-soluble); and
• Hole 8 hit 230 ft. of 0.51% copper (0.47% acid-soluble).

  These results also confirm the leachability of the copper, Summo states, adding that assays from the nearby Burro deposit are still pending.

  Preliminary results of column leach tests on bulk material indicate recoveries of 42-67% in 38-59 days; the company anticipates recoveries to fall in the 70-80% range over 100-150 days.

  Summo management is trying to raise funds to expand the mine and is in talks with several institutions regarding debt financing. If funds are secured, Summo says, production could begin by mid-1999 at an annual rate of 17 million lbs. cathode copper.

  Johnson Camp is an open-pit, heap-leach, solvent extraction-electrowinning operation. Proven and probable reserves in the Copper Chief and Burro deposits combined are estimated at 27.8 million tons grading 0.387% copper at a stripping ratio of 0.76-to-1. Additional resources are said to exist outside the reserve areas.

  Cash operating costs are pegged at US63-68 cents per lb. of cathode copper. Initially, a capital investment of US$7.5 million will be required to restart the mine, Summo estimates. This figure does not include the mining fleet, which will be provided by a contractor.

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