Sherman Mine (General Sherman), Alleghany, Alleghany Mining District (Forest Mining District), Sierra County, California, USAi

Regional Level Types
Sherman Mine (General Sherman)	Mine
Alleghany	- not defined -
Alleghany Mining District (Forest Mining District)	Mining District
Sierra County	County
California	State
USA	Country

A former Au occurrence/mine located in the NW¼ sec. 3 & in the NE¼ sec. 4, T18N, R10E, & in sec. 34, T19N, R10E, MDM, 0.9 km (0.5 mile) SSW of Alleghany, along the N canyon wall of Kanaka Creek, on National Forest land. MRDS database stated accuracy for this location is 1,000 meters. Adjoins the Nevada Mine group.

NOTE: There are 3 USGS MRDS files pertaining to this locality. One is for the "Sherman" and two are for the "General Sherman." They all have approximately the same geographic coordinates. All 3 MRDS files place this mine in secs. 3 & 4, and MRDS file #10103110 adds sec. 34, T19N (a contiguous section) as well.

Mineralization is a vein deposit hosted in gabbro, slate, serpentinite, granite.

Description of the ore body as per USGS MRDS file #10103110: The ore body strikes N18W and dips dips 60W (or strikes N05W and dips 50W) at a thickness of 3.66 meters. A sinuous vein strikes N to N36W and averages 3 feet in thickness and is comprised of white quartz that is slightly iron-stained & sometimes with small inclusions of schist and rarely small patches of pyrite associated with minute arsenopyrite crystals. Pyritic gouge streaks parallel the walls. The vein is well-defined for 700 feet and crosses nearly horizontal quartz stringer that pinches out after 450 feet. Beyond the pinchout are small, discontinuous stringers of quartz up to 50 feet from the face, where a 1 foot thick vein enters.

An alternate description of the ore body is provided in USGS MRDS file #10034776: The ore body strikes N05W and dips 50W. The vein is irregular with several branching strands. Minor faults occur nearly parallel to the vein and carry some quartz. Post-quartz movement in the plane of the vein is evident. Grooving strikes N57E. The quartz is commonly "watery" to white or rusty with abundant vugs. Later quartz occurs as minute veinlets perpendicular to the vein. The average dip is 35-65W. 3 veins outcrop with 70 feet between the uppermost and the lowest. Irregular stringers of granite occur 300 feet E of the portal. The country rock is coarse to fine-grained gabbro, less schistose than usual. A narrow belt of quartzitic slate occurs between the gabbro and serpentine belt 400 feet to the E. The vein is entirely in gabbro. Local alteration includes carbonate. Local rocks include Mesozoic gabbroic rocks, unit 2 (undivided).

Workings include underground openings with an overall depth of 30.48 meters and an overall length of 670.56 meters and comprised of a 1,000 foot (1,200 foot) adit.

Production data are found in: MacBoyle, Errol (1920b).

No other production record was found.

Other Regions, Features and Areas containing this locality

References