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Uncle Sam Mine (Hardscrabble Mine; Old Dominion Mine), Mount Benedict, Nogales Mining District (Gold Hill Mining District), Santa Cruz County, Arizona, USAi
Regional Level Types
Uncle Sam Mine (Hardscrabble Mine; Old Dominion Mine)Mine
Mount BenedictMountain
Nogales Mining District (Gold Hill Mining District)Mining District
Santa Cruz CountyCounty
ArizonaState
USACountry

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Latitude & Longitude (WGS84):
31° 23' 36'' North , 110° 54' 44'' West
Latitude & Longitude (decimal):
Type:
Nearest Settlements:
PlacePopulationDistance
Beyerville177 (2011)3.2km
Nogales20,252 (2017)6.2km
Nogales212,533 (2018)9.8km
Kino Springs136 (2011)10.3km
Rio Rico18,962 (2011)10.6km
Mindat Locality ID:
33936
Long-form identifier:
mindat:1:2:33936:7
GUID (UUID V4):
0


‡Ref.: Schrader, F.C. & J.M. Hill (1915), Mineral deposits of the Santa Rita and Patagonia Mountains, Arizona, USGS Bull. 582: 351-352.

Keith, Stanton B. (1975), Arizona Bureau of Mines Bull. 191, Index of Mining Properties in Santa Cruz County Arizona: 61 (Table 4).

U.S. Bureau of Mines field notes AU10.

Arizona Bureau of Mines file data.

MRDS database Dep. ID file #10210938, MAS ID #0040230088.

A former underground Pb-Ag-Au-Cu mine located in the SW¼SE¼SE¼ sec. 28, T.23S., R.14E., just across the gulch, 300 feet east of the Dura Mine, on private land. W.C. Ellis, of Nogales; Hogan; Driscoll; Stump & Frame; Hudgin; and the Red Rock Mining Co. had unspecified involvement here (1975).

Mineralization is shear veins of roughly banded quartz and brecciated, altered Jurassic quartz monzonite wall rock with largely oxidized argentiferous and auriferous galena and minor chalcopyrite. Many associated dikes.

The vein is in the quartz monzonite and appears to be the same vein as at the Dura Mine. It trends N.75ºE., though the dip continues steep (75º) to the north, as at the Dura Mine. The vein is said to contain 4 inches of ore-bearing quartz on the hanging wall and 6 inches (15 cm) on the footwall. The ore carries Pb, Au & a little Ag.

In the gulch bewteen the Dura and the Uncle Sam Mines, the quartz monzonite is intruded by dioritic, aplitic, and dark basic dikes, some of which are apparently lamprophyric.

Workings include shafts and drifts. The deepest shaft is reported at 345 feet. Prospected and worked for gold in the mid-1800's and sporadically until 1967. Estimated and recorded production of some 250 tons of ore averaging about 9% Pb, 8 oz. Ag/T, and minor Cu.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


2 valid minerals.

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
Chalcopyrite2.CB.10aCuFeS2
Galena2.CD.10PbS
var. Silver-bearing Galena2.CD.10PbS with Ag

List of minerals for each chemical element

SSulfur
S ChalcopyriteCuFeS2
S GalenaPbS
S Galena var. Silver-bearing GalenaPbS with Ag
FeIron
Fe ChalcopyriteCuFeS2
CuCopper
Cu ChalcopyriteCuFeS2
AgSilver
Ag Galena var. Silver-bearing GalenaPbS with Ag
PbLead
Pb GalenaPbS
Pb Galena var. Silver-bearing GalenaPbS with Ag

Other Databases

Link to USGS MRDS:10210938

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