Three R mine

Also known as Colossal Mine

There is a large amount of material in the Arizona Department of Mines and Mineral Resources Mining Collection,
see http://docs.azgs.az.gov/OnlineAccessMineFiles/S-Z/ThreerminegroupSantacruz38a-1.pdf,
http://docs.azgs.az.gov/OnlineAccessMineFiles/S-Z/ThreerminegroupSantacruz38a-2.pdf,
http://docs.azgs.az.gov/OnlineAccessMineFiles/S-Z/ThreerminegroupSantacruz38a-3.pdf

[Ref. 2]

Ownership

Richardson, Amster, Three-R Mg. & Mllg. Co., Three-R Mines Inc., Border Mines Inc., Bird, Colossal Mines, Taylor & Barclay⁵

Location

31.4839 N, 110.7633 W³

23S 15E Cen. 36⁵

Mineral Products

Cu, Ag-, Pb-, Zn-, Mn-⁵

Geology

Large, steeply dipping, lensing orebody, of disseminated cupriferous pyrite with minor chalcopyrite, bornite, and minor lead and zinc, along a fault zone intersected by numerous fractures. Zone is strongly oxidized and supergene enriched to high grade chalcopyrite and some covellite. Wall rock is a shattered and altered Jurassic granite which contains disseminated pyrite and sparse copper mineralization in quartz-sericite veinlets around the orebody. Alunite masses occur in the fault zone.⁵

Type of Operation

Tunnel and shaft operations. Located in the late 1800's but mined mainly from 1908 through 1956, producing some 130,000 tons of ore averaging about 4% Cu with minor Ag, Pb, Zn, and Au⁵.

Environmental Issues

^{[Ref. 8]}.

Daily Star article,

^{[Ref. 9]}.

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