Geologic descriptionThe Stay property is in schist, slate, phyllite, tuff, and quartzite that is cut by Cretaceous quartz porphyry dikes that are exposed along the ridge east of Eva Creek (Newberry and others, 1996). Gold-quartz veins are found within the schist. Hill (1933, p. 129-133) visited the Stay property in 1931, and the following is a summary of his observations. During 1930 and 1931, about 700 tons of ore were produced from an adit and the Stay shafts that yielded $16,000 in gold (about 774 ounces). Most of this ore had an average grade of a little more than an ounce of gold per ton. Several shafts on the Little Eva and Eva No. 2 claims carried as much as $60 to $70 per ton in gold (about 2.9 to 3.4 ounces of gold per ton). Most of the development work was in the Little Eva adit near the mouth of Eva Creek. By 1931, this adit was 570 feet long. The adit followed a badly faulted, 6- to 8-inch-wide, vertical vein striking N 27 W. The vein was continually offset to the west by a series of faults that had a strike of N 10-51 E and a 30 to 70 degrees, north to northwest dip. Below the tunnel, the vein was developed by several winzes; the vein exposed in them was 8 to 11 inches wide. In some places the schist wall rock east of the main vein was cut by numerous stringers of quartz that followed the nearly horizontal planes of schistosity. The schist contained from 23 cents to as much as $1 in gold per ton (about 0.01 to 0.05 ounce of gold per ton). Considerable work was also done near the northwest corner of the Little Eva claim and the northwestern part of the Eva No. 2 claim. Several shafts from 12 to 60 feet deep were scattered over an area of about 200 square feet. The Eva No. 2 shaft was 60 feet deep and had about 40 feet of drifting at the 40-foot level. The shaft was sunk on a short segment of the vein between two parallel faults. The vein was from 4 to 6 inches wide and trended N 50 W; it was high grade, and the schist on both sides was mineralized. Samples of gold are 778, 811, and 831 fine (Glover, 1950). |