State: New Mexico
Elevation: 6,896 feet
The Alberta mine in 1924 was being worked under option by the Mogollon Mines Co. The vein, known as the Ida May, strikes about N. 40° W. in its southern part, near the Little Fanney Mine, and dips 60°-65°SW. At the south end the outcrops are obscure and the vein is not well defined on the surface. Apparently there are two branches, one joining the Fanney a short distance west of the Queen vein and the other uniting with the Queen north of the northern branch of the Fanney. The first has been developed underground from the Little Fanney workings. Northwestward across Fanney Hill the outcrop is nowhere prominent, and on the northwestern part of the hill, above the workings of the Alberta mine, where the vein is best exposed, it shows very fine grained quartz of chalcedonic appearance varied in places by hackly quartz. Development work on the Alberta mine shows that this material passes in depth into quartz of the productive type, associated with sulphides.
Northwestward as far as the 7,200-foot contour both walls of the vein are in andesite, and the vein is irregular in detail. Beyond point the footwall is rhyolite and sharply defined, but the andesite hanging wall is much brecciated and penetrated by small stringers. The vein here splits; the northern branch continues in the same direction and is known as the Independence, but the southern branch strikes a few degrees north of west, parallel to the Fanney vein. The southern branch near the junction is about 4 feet wide and consists of hackly quartz without calcite or fluorite. Farther west the vein, though traceable along the outcrop, is nowhere conspicuous. It consists chiefly of fine-grained quartz, though at a prospect north of the Johnson calcite is dominant. From this prospect to its west end the outcrop shows a width of less than a foot, principally of fine-grained quartz.
The mine was first developed by an adit that cut the vein not far from its junction with the Independence vein, at an altitude slightly higher than the collar of the Little Fanney shaft. The vein has been developed on the adit level for about 300 feet northwestward from its junction with the Independence vein. At the outcrop the vein is in the Last Chance andesite on both walls; at the tunnel level the footwall rock is Fanney rhyolite. The average strike is about N. 40° W., and the dip 60°-65° SW. The vein is well defined and over most of the distance developed exceeds 5 feet in width.
For 200 feet northwestward from the junction the drift is in ore, said to have in places a tenor exceeding 70 ounces of silver to the ton. There has been no postmineral faulting and, although the depth below the surface is less than 300 feet, practically no oxidation. The ore consists of alternate bands of calcite and quartz with finely disseminated sulphides and is similar in general-appearance to the sulphide ore of the Little Fanney and Last Chance mines, but the metallic minerals are more finely divided. In the low-grade material northwest of the ore shoot calcite predominates. Recently a shaft has been sunk in ore to a depth of more than 100 feet. .
At the northwest end of the drift a 30-foot winze has been sunk, and a short crosscut runs southwest from it and this cuts a 4-inch vein of chalcopyrite, partly oxidized to malachite and azurite.
Since the mine has been worked by the Mogollon Mines Co. operations except for the shaft below the adit level have been conducted from the Little Fanney mine. Work carried on from the 200, 500, and 700 foot levels of the Little Fanuey has revealed a large ore body with an apparent southerly pitch. The grade of the ore is equal to that of the ore bodies of the Littlse Fanney and Last Chance, though the average width of the vein is less.
Source: Geology and Ore Deposits of the Mogollon Mining District New Mexico. USGS Bulletin 787, 1927