Montana Mine group

See Ruby, Arizona by Bob & Al Ring, and Tallia Pfrimmer Cahoon for many details.⁷

Mining District and Mines

Oro Blanco District

Location

?⁵

Mineral Products⁶

Pb, Zn, Ag, Cu, (Cd, Sb, As)

Ownership⁶

Owner Names: Rough & Ready, Orion Co., Montana Co., Zeckendorf, Goldfield Consolidated Mines Exploration Co., Montana Mines Operations, Eagle-Pincher Mg. and Smltg. Co., Miller, Maravilla Mineros Corp.

Type of Operation and Production⁶

Extensive operations from shafts. Located in the early 1870's and worked intermittently on a small scale until 1928 through 1940. Some sporadic work up to 1958. Total production would be some 870,000 tons of ore averaging about 3.5% Pb, 3.5% Zn, 5 oz. Ag/T, 0.5 oz. Au/T, and 0.3% Cu.

Geology⁶

Lensing, vuggy, quartz veins containing sphalerite, pyrite, galena, chalcopyrite and tetrahedite as fracture fillings, in vugs, and as replacements of quartz and sheared and brecciated wall rock. En echalon veins are along a fault zone cutting blocks of Cretaceous conglomerate and Laramide diorite that are intruded and offset by later diorite porphyry dikes. Sulfides oxidized near the surface with enrichment of silver and gold.

References

1. Mineral Appraisal of Coronado National Forest, Part 12, Santa Rita Mountains Unit, MLA11-94 (1994). SR 591-609
   https://data.azgs.arizona.edu/api/v1/collections/BMRI-1552428987530-264/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. https://westernmininghistory.com/mine-detail/10162214/
6. Index of Mining Properties in Santa Cruz county, Arizona; Stanton B. Keith, Arizona Geological Survey, Bulletin 191 (1975).
7. Ruby, Arizona - Mining, Mayhem, and Murder by Bob & Al Ring, and Tallia Pfrimmer Cahoon; U.S. Press & Graphics