Northern Spy Mine, East Tintic Mining District, Utah County, Utah, USAi

Regional Level Types
Northern Spy Mine	Mine
East Tintic Mining District	- not defined -
Utah County	County
Utah	State
USA	Country

Location and Description

The Northern Spy mine is located on the south eastern slopes of Mammoth peak. The mine is operated by a 900 foot deep shaft, with the collar at an altitude of 7,390 feet. There are many prospect drifts on levels 7, 8, and 9, but no large ore bodies were discovered. On the 700 foot level, the Sioux Ajax tunnel connects the Northern Spy mine to the neighboring Carisa mine. Both the Northern Spy and Carisa mines were owned by the Carisa (Mining?) company, with their dividends amounting to $60,000. Both properties yielded Pb, Ag, Au, and Cu. Although the Northern Spy and Carisa mines are close together, they are in different counties, with the border running in between them, resulting in the Northern Spy being in Utah county, and the Carisa being in Juab county.

Geology

A few hundred feet north of the shaft, the limestone of the Humbug formation ceases, and above the shaft to the north, the light blue Pine Canyon limestone is exposed. On the 500 foot level, the Gardner dolomite, and it's black carbonaceous bed are exposed just 25 feet above the level, to the northwest. All of the area south of the shaft is composed of the Bluebell dolomite.

Workings and Ore

On the 100 foot level, a flat stope was worked for 250 feet, and the ore contained galena and cerussite, which was fairly rich in silver. South of the shaft, the ore bodies follow fissures. The ores in the fissures contained much copper, which was originally enargite, but is partly oxidized, and there is a lot of gangue baryte. The fissures that carry the ore are inconspicuous, with the ore spreading from them by replacement of dolomite. Oxidized copper ore cropped out 400 feet south of the shaft along several fissures. The upper stopes did extend past level 4, and the fissures trend north 20° east, and are nearly vertical. On level 6, 540 feet below the ground and near the shaft, a body of copper ore was encountered that continued down to level 7. The ore yielded 12% copper, much iron, a little silver, and very little gold. The ore was largely oxidized, and contained copper arsenates in honey combed quartz, and in some places azurite and malachite that partially replaces the dolomite. The ore did not contain lead, although 1 ton of galena was found in the ore shoot. Dolomite or limestone that is silicified surrounds there shoot. Exploratory crosscut son the east side line, near the iron blossom ore shoot, discovered vein matter and Silicified limestone with low gold content.

Other Regions, Features and Areas containing this locality

References