Ventura mine group

A former underground Cu-Ag-Au-Pb-Mo mine located in the center sec. 36, T22S, R15E, near the Three-R Mine, on National Forest land. A new property circa 1915. Orebody reportedly 30 feet wide. Ore assays at 8% Cu, $4 Au/T (period values), and 8 oz. Ag/T¹⁰.

Ownership

unclear

Location

31.47722,-110.76694¹⁰

22S 15E Center sec. 36¹⁰

Mineral Products

Cu, Ag, Pb, Zn-, Au-, Mn-⁵

Geology

Quartz-gouge veins with spotty pyrite, chalcopyrite, chalcocite, and minor galena and sphalerite, roughly banded, along fissures and joints in strongly silicified and weakly mineralized Precambrian metamorphosed volcanics and sediments intruded by Jurassic granite. Oxidation produced abundant iron oxide and psilomelane.⁵

Type of Operation

Tunnel operations. Sporadic production in 1913 and from 1933 through 1950, produced some 440 tons of ore averaging about 6% Cu, 16 oz. Ag/T, 15 Pb, and 0.2 oz. Au/T⁵.

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. Mike Bertram, 11/21/23
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 Staton B. Keith, bulletin 1991, Arizona Geological Survey, 1975
6. Geology of the Three R Mine, Palmetto Mining District, Santa Cruz County, Arizona by Paul Handverger, MS thesis 1963, University of Arizona
7. https://mrdata.usgs.gov/mrds/show-mrds.php?dep_id=10046338
8. https://azdeq.gov/Three-R-Mine
9. https://tucson.com/news/local/three-r-mine-contributed-to-arizonas-rep-for-copper-production/article_2a25e1e1-7280-5fd5-be97-a40732a39b1b.html
10. mindat.org