Hancock Mine

The Hancock Mine is 2 miles west of Greaterville and a mile east of the Mountain King mine. It is on a 3 foot quartz vein in granite. The vein dips to the west and is opened mainly by a 100 foot shaft which shows galena and pyrite. The mine was worked by W. M. Robinson in 1885 and is reported to have shipped some rich ore carrying lead carbonate and horn silver².

Mining District and Mines

Greaterville District

USBM: Historical: Worked in 1885, shipped a small amount of high grade Pb - Ag ore; ¹

Location

SE¼. sec. 14, T. 19 S., R. 15 E.¹

E. Cen. sec. 14, T. 19 S., R. 15 E.⁶

31.78152N, -110.77512W¹

Mineral Products

Pb, Zn, Ag, Cu-, Au-⁶

USBM: samples 138. Ag 270 ppm, Au 260 ppb, Bi 222 ppm, Cr 800 ppm, Cu 1,150 ppm, Pb 9220 ppm, Zn 630 ppm¹.

Geology

Irregular quartz vein containing spotty, partially oxidized, base metal sulfides, and rich, near surface, cerussite and cerargyrite. Vein cuts Precambrian granodiorite⁶.

Quartz vein cutting granite. Vein is vuggy and contains pyrite, galena, limonite, and haematite ¹.

Type of Operation and Production

Shaft workings. In late 1800s produced a small tonnage of high grade Pb - Ag ore⁶.

Shaft 100 ft. deep. USBM: shaft flooded at 15 ft. depth.³

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, U.S. Department of Interior, 1915. Republished 2014 by Kerby Jackson.
3. mindat.org
4. USGS Mineral Resources Data System - possibly using NAD72 (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. Index of Mining Properties in Pima County by Stanton B. Keith, bulletin 189, Arizona Geological Survey, 1974