Philadelphia

The Philadelphia prospect is north of the Anaconda Camp, on open ground. It was first worked in 1873, and John Parks is said to have shipped from it in 1882 to the smelter at Socorro, N.M., two car loads of ore that averaged 300 ounces of silver to the ton. It is on a strong vein which dips 70° SSW in red tuffaceous andesite and is opened by several shafts and drifts. The two deepest shafts are said to be 90 feet deep and the other 60 feet. Water stands about 50 feet below the surface. The main shaft makes considerably more water than could be practically handled with a horse whim.

The croppings of the vein, which are not prominent, consist of iron-stained quartz and barite and in some places show considerable malachite and azurite, The vein is about 2½ feet in width. It is banded and in the oxidized zone is composed mainly of a barite - quartz gangue and the ore minerals, galena and gray copper. The surface ore is all oxidized and carries lead and copper carbonates in a mixture of limonite - stained quartz and barite. Its value was principally in copper and silver, the latter probalby carried in the chloride or bromide form. The deeper ores were composed of argetiferous galena and gray copper.

The mine is part of the Anaconda group.

Alternate Names

None

Company

John Parks, Anaconda-Arizona Mg. Co., Altamirano, Boulder Mg. Co.⁵

Mining District

Wrightson District

Location

21S 15E, NW¼ Cen. S., Cen. & SW¼ 3 N. Cen. & NE¼ 10⁵

Mineral Products

Ag, Pb, Cu, Zn-, Au- ⁵

Geology

Lensing quartz fissure veins containing calcite and barite, and with shoots, stringers, and seams of argentiferous galena, chalcopyrite, sphalerite, tetrahedrite and pyrite. Veins are often vuggy with mineralization banded or lining vugs. Wall rock is Triassic rhyolite and latite volcanics [Anaconda Group as a whole].⁵

Type of Operation and Production

Tunnel and shaft operations. Worked from early 1870s and intermittently through 1949, producing some 300 tons of ore averaging about 5% Pb, 30 oz. Ag/T, 3% Cu, and minor Au. [Anaconda Group as a whole]⁵

References

1. Mineral Appraisal of Coronado National Forest, Part 12, Santa Rita Mountains Unit, MLA11-94 (1994). SR 591-609
   http://repository.azgs.az.gov/sites/default/files/dlio/files/nid1813/usbm_mla_011-94.pdf
2. Mining in the Santa Rita and Patagonia Mountains of Arizona, F. C. Schrader, U.S. Department of Interior, 1915. Republished 2014 by Kerby Jackson.
3. Mike Bertram,
4. USGS Mineral Resources Data System - using WGS84 (https://mrdata.usgs.gov/mrds/map-commodity.html#home)
5. Index of Mining Properties in Santa Cruz County by Stanton B. Keith, bulletin 1991, Arizona Geological Survey, 1975
6. WesternMiningHistory.com