Rayrock completes mine plan for Daisey

A final mine plan has established a minable reserve of 11.4 million tons grading 0.018 oz. gold per ton for the Secret Pass gold deposit.

The deposit is part of the Daisy gold project near Beatty, Nev., held 75% by Inter-Rock Gold (ME). Project operator Rayrock Yellowknife Resources (TSE) has a 25% stake in the property, which lies halfway between Las Vegas and Tonopah in Nye Cty.

Secret Pass is a combined oxide-sulphide deposit in the Tertiary-age Crater Flat tuff. Considering its large tonnage and low grade, the deposit should be amenable to open-pit mining and heap leaching.

The 11.4-million-ton reserve figure replaces an earlier 7.1-million-ton estimate at the same grade. Rayrock says this higher figure was arrived at based on an increased production rate and shorter mine life. The companies believe additional mineralized material will move into the ore-reserve category as development provides more information. Feasibility work continues.

Current reserves represent only the oxidized zone of the deposit. Sulphide mineralization, together with additional oxide mineralization that can be exploited by a larger open pit, would raise the reserve figure to 17.9 million tons grading 0.021 oz. Rayrock is awaiting results of metallurgical testing on the sulphides, which may be treated by bio-oxidation to remove sulphides.

Work has continued on three of the other four known occurrences on the property: delineation drilling at the West zone; large-scale sampling at the Mother Lode pit; and exploration drilling of the new Joshua zone.

West zone

At the West zone, about 1 mile southwest of the Secret Pass deposit, an additional 15 holes have been drilled to delineate the mineralized body. The structure has been traced 700 ft. along strike, and its horizontal width averages 125 ft. The mineralized zone dips north at 55!, and has been intersected at 300 ft. below surface.

Rayrock reports a preliminary mineral inventory of 1.2 million tons grading 0.03 oz. per ton, and says sufficient data are in hand to calculate a reserve figure for the zone. The West zone has oxide mineralization that would not require pretreatment before cyanidation.

Mother Lode

At the Mother Lode pit, about 2 miles northeast of Secret Pass, Rayrock has taken a 10-ton bulk sample of sulphide mineralization for metallurgical testing. The Mother Lode occurrence has a preliminary mineral inventory of 9.4 million tons grading 0.046 oz. gold per ton, but no reserve figures have been calculated.

Joshua zone

Another mile northeast of the Mother Lode pit, anomalous geochemical results have been followed up by drilling, where nine of 16 exploration drill holes intersected low-grade gold mineralization. The mineralization is near the surface in the same tuff unit that hosts the Secret Pass deposit.

The new zone has surface dimensions of 1,000 by 1,200 ft.; the best intersection in the exploration holes was 135 ft. long and contained 0.011 oz. gold per ton.