The Mount Union Mine is a lead and gold mine located in Yavapai county, Arizona at an elevation of 7,201 feet.
About the MRDS Data:
All mine locations were obtained from the USGS Mineral Resources Data System. The locations and other information in this database have not been verified for accuracy. It should be assumed that all mines are on private property.
Mine Info
Elevation: 7,201 Feet (2,195 Meters)
Commodity: Lead, Gold
Lat, Long: 34.40444, -112.41444
Map: View on Google Maps
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Mine Description
The holdings of “Trapshooter” Reilly Gold Mines include the old Crook, Venezia, Starlight, and Mount Union mines, in Crooks Canyon. These mines are in the vicinity of Venezia post office, which, via the Senator Highway, is 15 miles from Prescott.
During the early days, these mines were rather extensively worked in the oxidized zone, which was generally from 40 to less than 200 feet deep. Later, sulphide ores were mined and treated in a 20-stamp amalgamation-concentration mill at Venezia and in the Mount Union mill. Much of this work was done by the late J. B. Tomlinson and lessees. From 1927 to about 1932, the property was held by the Westerner Gold-Lead Mining Company which, according to the U. S. Mineral Resources of 1930, milled about 100 tons of gold ore and shipped one car of lead-zinc ore. Since about 1932, the property has been held by “Trapshooter” Reilly Gold Mines. This company shipped some bullion and concentrates, but suspended operations in September, 1933.
The total combined production of these mines probably does not exceed $500,000. (57)
This area is composed of ridges and canyons with altitudes of 6,200 to 7,400 feet. It lies in the granite belt that extends southward through Mount Union and contains many dikes of rhyolitic to basic composition.
Mount Union mine: (60) The Mount Union mine, a quarter mile southwest of the summit of Mount Union, at an altitude of 7,400 feet, is accessible by a road that branches eastward at the divide. In 1906, this mine yielded lead ore with gold and silver. A small Huntington mill was operated for a short time, but the total production of the mine was not large.
Here, the rock is Bradshaw granite, cut by many dikes of rhyolite-porphyry. Two veins are reported to occur on the property, one of them from 6 to 10 feet wide, but they do not show well at the surface. Material on the dump shows pyrite, galena, and sphalerite in quartz. According to local reports, the ore was of low grade and the gold difficult to amalgamate.
(57) Lindgren, W., work cited, pp. 123–25.
(60) Abstracted from Lindgren, W., work cited, p. 125.
Text from Arizona Lode Gold Mines and Gold Mining, Arizona Bureau of Mines. Original 1934, revised 1967
Mount Union Mine MRDS details
Site Name
Primary: Mount Union Mine
Commodity
Primary: Lead
Primary: Gold
Secondary: Copper
Secondary: Silver
Secondary: Zinc
Location
State: Arizona
County: Yavapai
District: Mount Union District
Land Status
Land ownership: National Forest
Note: the land ownership field only identifies whether the area the mine is in is generally on public lands like Forest Service or BLM land, or if it is in an area that is generally private property. It does not definitively identify property status, nor does it indicate claim status or whether an area is open to prospecting. Always respect private property.
Holdings
Not available
Workings
Type: Underground
Ownership
Not available
Production
Not available
Deposit
Record Type: Site
Operation Category: Producer
Operation Type: Unknown
Years of Production:
Organization:
Significant: N
Deposit Size: S
Physiography
General Physiographic Area: Intermontane Plateaus
Physiographic Province: Basin And Range Province
Physiographic Section: Mexican Highland
Mineral Deposit Model
Not available
Orebody
Form: TABULAR
Structure
Type: R
Description: Foliation In Precambrian Rocks Trends N35e To N45e
Type: L
Description: Dikes And Veins Parallel Foliation
Alterations
Alteration Type: L
Alteration Text: None
Rocks
Name: Rhyolite
Role: Associated
Age Type: Associated Rock Unit
Age in Years: 1760.000000+-
Dating Method: U-Pb (zircon)
Material Analyzed: Zircon
Age Young: Proterozoic
Analytical Data
Not available
Materials
Ore: Chalcopyrite
Ore: Sphalerite
Ore: Galena
Ore: Tetrahedrite
Gangue: Quartz
Unknown: Pyrite
Comments
Comment (Commodity): GOLD DIFFICULT TO AMALGAMATE
Comment (Production): ITEM ( 8 ) IS ESTIMATED FROM $ 125,000 PRODUCTION AT $ 20.67 PER OUNCE.
Comment (Geology): DEPOSIT IS VEIN WHICH CUTS PRECAMBRIAN GRANODIORITE. RHYOLITE PORPHYRY DIKES OF PROBABLE CRET-TERT AGE ASSOCIATED WITH VEINS
References
Reference (Deposit): USGS BULL 782, P. 125
Reference (Production): A.B.M. BULLETIN 140 , P. 101 .
Reference (Deposit): ELSING, M.J. AND HEINEMAN, R.E., 1936 , ARIZONA METAL PRODUCTION: ARIZONA BUREAU OF MINES BULLETIN 140 , P. 101
Reference (Deposit): ABGMT AND ADMR FILE DATA
Arizona Gold
"Where to Find Gold in Arizona" looks at the density of modern placer mining claims along with historical gold mining locations and mining district descriptions to determine areas of high gold discovery potential in Arizona. Read more: Where to Find Gold in Arizona.
