The Midnight Test Mine is a gold mine located in Yavapai county, Arizona at an elevation of 7,001 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: 7,001 Feet (2,134 Meters)
Commodity: Gold
Lat, Long: 34.47389, -112.40194
Map: View on Google Maps
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Mine Description
The Midnight Test mine, held by the National Gold Corporation, is on the northwestern slope of Spruce Mountain, at an elevation of 7,000 feet. According to local people, this mine was worked to shallow depths during the early days and Was developed by a 400-foot shaft prior to 1906. For a short While during this period, a small mill operated on the property. In 1919, the mine yielded some milling ore. The total production prior to 1922 is reported to be $100,000, part of which came from a rich shoot of silver ore near the surface. Subsequently, the property was obtained by the National Exploration Company, later the National Gold Corporation, which has carried on considerable underground exploration and built a 200-ton mill designed for amalgamation, flotation, and table concentration. The National Gold Corporation has made several shipments of ore and concentrates.
The principal rocks of the vicinity consist of schist, intruded by stocks and dikes of granodiorite and When visited in January, 1934, the main shaft was 600 feet deep, on an incline of 80° W., and the workings seen followed a shear zone that trends N. 15°-20° W., mainly in the schist. The fractured portions of this zone are generally marked by abundant limonite and hematite. No manganese dioxide was seen. In some places, irregular to lenticular, generally narrow Veins of coarse-grained, druzy quartz are present. This quartz contains scattered kernels of galena and, mainly below the 300-foot level, bands and scattered bunches of pyrite with minor amounts of sphalerite. Gold is reported to occur mainly in the iron oxides of the shear zone and to a less extent in the quartz and sulphides.
Text from Arizona Lode Gold Mines and Gold Mining, Arizona Bureau of Mines. Original 1934, revised 1967
Midnight Test Mine MRDS details
Site Name
Primary: Midnight Test Mine
Secondary: National Gold
Commodity
Primary: Gold
Secondary: Silver
Secondary: Lead
Secondary: Copper
Tertiary: Zinc
Location
State: Arizona
County: Yavapai
District: Groom Creek 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
Owner Name: National Gold Co
Production
Not available
Deposit
Record Type: Site
Operation Category: Producer
Operation Type: Unknown
Year First Production: 1902
Year Last Production: 1935
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: LENTICULAR
Structure
Type: R
Description: Foliation In Precambrian Rocks Trends N10e To N20e
Type: L
Description: Veins Parallel Foliation And Crosscut It By 10-20 Deg, Trending N20e To N-S
Alterations
Alteration Type: L
Alteration Text: Minor
Rocks
Name: Rhyolite
Role: Associated
Age Type: Associated Rock
Age Young: Late Cretaceous
Analytical Data
Not available
Materials
Ore: Galena
Ore: Gold
Ore: Sphalerite
Gangue: Quartz
Unknown: Pyrite
Comments
Comment (Location): LOCATED ON NORTH SLOPE OF SPRUCE MOUNTAIN
Comment (Workings): MAIN SHAFT LOCATED ON MIDNIGHT TEST CLAIM; NUMEROUS OTHER SHAFTS ON ADJOINING CLAIMS
Comment (Geology): DEPOSIT IS QUARTZ VEIN WHICH CUTS PROTEROZOIC ROCKS
Comment (Production): ITEM ( 8 ) IS ESTIMATED FROM $ 75,000 PRODUCTION AT $ 20.67 PER OUNCE.
Comment (Development): 20 CLAIMS OF WHICH THE MAJOR PATENTED CLAIMS ARE THE MIDNIGHT TEST, DIXIE, AND SAXON
References
Reference (Deposit): WILSON, E.D., 1934 , ARIZONA LODE GOLD MINES AND GOLD MINING: ARIZONA BUREAU OF MINES BULLETIN 137 , P. 32
Reference (Deposit): ELSING, M.J. AND HEINEMAN, R.E., 1936 , ARIZONA METAL PRODUCTION: ARIZONA BUREAU OF MINES BULLETINS 140 , P. 102
Reference (Deposit): ARIZONA DEPT OF MINERAL RESOURCES FILE DATA
Reference (Deposit): ABGMT CLIPPINGS FILES
Reference (Deposit): ABGMT-USBM FILE DATA
Reference (Production): A.B.M. BULLETIN 140 , P. 102
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.
