American Bonanza revs up Gold Bar rigs

Junior American Bonanza Gold Mining (BZA-V) will shortly resume drilling at the Gold Bar property in the Battle Mountain trend of Nevada.

The core program will immediately extend a reverse-circulation hole that was drilled in the summer. The hole, which bottomed at 4,200 ft. down, returned anomalous gold, arsenic and silver values over wide widths, all of which are characteristic of Carlin-type gold deposits.

Also, near the hole’s bottom, fracturing and alteration increased in the Lone Mountain dolomite unit. This may be indicated of close proximity to the favourable Robert’s Mountain formation.

Several other targets will be tested using results from an ongoing geophysical survey.

Between 1987 and 1994, Gold Bar produced 485,000 oz. from 7.5 million tons grading 0.074 oz. per ton. Recoveries are said to have averaged 87%.

American Bonanza also has staked an adjacent property that covers 600 acres of favourable structural and stratigraphic targets. The property, which has been mapped, is being incorporated in the geophysical survey.

American Nevada Gold (AGN-V) owns a 5% stake in property.

Meanwhile, American Bonanza is sending a second underground rig and one surface rig to its Copperstone property in Arizona. Current drilling is focused on existing resources in order to bump them up to reserve status.

Earlier this year, the company extended an existing decline some 500 ft. to the southern end of the targeted D zone, which is 600-650 ft. below surface. The extension was made to intersect drill hole C96-19, which returned 5.3 oz. over 10 ft., about 80 ft. north of D zone’s southern margin.

A 1999 scoping study by MRDI Canada estimated the total geological resource for the C and D zones at 2.1 million tons grading 0.34 oz. The D zone alone contains 391,500 oz. in an indicated and inferred resource totalling 910,800 tons and averaging 0.43 oz.

Gold grades were capped at 4.7 oz. in the D zone and at 2.5 oz. in the C zone.

Between 1987 and 1993, Cyprus Minerals pulled 514,000 oz. from 5.6 million tons of milling ore and 1.2 million tons of leaching ore using open-pit mining methods. The carbon-in-pulp mill recorded recovery rates of 89%.

Following the mine’s closure, the tailings pond was reclaimed and the CIP mill removed. Some facilities, such as roadways and power lines, remain in service.

In 1993, Santa Fe Pacific entered the picture and proceeded to drill 12,500 ft. in 17 widely spaced reverse-circulation holes. A deep, 1,000-ft. vertical hole drilled from the pit cut 15 ft. grading 0.65 oz. gold per ton in the footwall of the Copperstone fault at 479 ft. from surface. The hole was never followed up, and the lease was terminated in 1994.