Summo boosts reserves

The resource estimate for the Lisbon Valley copper property in eastern Utah has doubled.

mmo Minerals (VSE), which is acquiring the asset from a private owner, reports the new estimate as being 38.4 million tons grading 0.48% copper. Summo is required to pay the vendor US$81,250 cash plus 2.4 million shares, half of which have been issued. The remaining 1.2 million shares are payable upon completion of a positive feasibility study.

The property contains three significant sandstone-hosted copper deposits, and Summo hopes to develop an open-pit, heap-leach operation which would incorporate solvent extraction-electrowinning.

Western Services Engineering compiled a fully diluted minable resource estimate for the Centennial and Sentinel deposits, while the estimate for the GTO deposit (including proven, probable and possible categories) was calculated by Summo.

Based on a cutoff grade of 0.1% copper, Centennial is estimated to contain 25.8 million tons grading 0.47% copper at a stripping ratio of 1.77-to-1. The nearer-surface Sentinel deposit contains about 6.3 million tons grading 0.31% copper at a stripping ratio of 0.31-to-1, also based on a 0.1% cutoff grade.

GTO, which is much deeper, contains an estimated 6.3 million tons grading 0.72% copper at a stripping ratio of 5.4-to-1 based on a cutoff of 0.3% copper.

These calculations are based on drill results from 1993 and do not include the 68 stepout holes drilled in 1994. Forty-eight of the holes contained visible copper over minable widths. Assays should be available by the end of January, at which time an updated resource will be calculated. In the meantime, Mountain State R & D is conducting metallurgical tests on bulk drill samples collected in 1993 and 1994.