Tightner Mine (Tightner Mines), 16 to 1 Mine (Sixteen-to-One Mine; Original Sixteen-to-One Mine), Alleghany, Alleghany Mining District (Forest Mining District), Sierra County, California, USAi

Regional Level Types
Tightner Mine (Tightner Mines)	Mine
16 to 1 Mine (Sixteen-to-One Mine; Original Sixteen-to-One Mine)	Mine
Alleghany	- not defined -
Alleghany Mining District (Forest Mining District)	Mining District
Sierra County	County
California	State
USA	Country

A former lode Au occurrence/mine located in sec. 34, T19N, R10E, MDM, 0.5 km (0.3 mile) ESE of Alleghany, along the North Fork Kanake Creek, near its confluence with the main channel, on National Forest land. MRDS database stated accuracy for this location is 100 meters.

The Sixteen-to-One and the Tightner shafts were originally the principal means of access for the two competing Sixteen-to-One mines and Tightner mines until the Tightner was acquired by the Sixteen to-One in 1924. Both saw continued usage until 1954 when a fire obstructed access in the Tightner shaft, after which the Sixteen-to-One shaft became the main mine access. The Tightner shaft was maintained for pumping, servicing, and ventilation (Carlson and Clark, 1956).

Local rocks include undivided pre-Cenozoic metavolcanic rocks, unit 2 (undivided).

Workings include underground openings.

The mine developed the Sixteen-to-One vein via two primary inclined shafts (technically winzes), the Sixteen-to-One and Tightner, and two main winzes, the 49 and 83. The Tightner shaft developed the northern half of the mine. The shaft is collared at the 250-foot level and then inclined to the east following the dip of the vein to the deepest level of the mine at 3,000 feet. The upper part of the shaft was driven at an angle of about 35? to only 2,100 due to limited hoist capacity. North and south drifts were driven every 100 feet to the 1,100-foot level, then every 200 feet to the 1,700-level. Limited exploratory drifts were driven at the 1,800-foot level in the hanging wall of the fault zone and within the fault zone at the 2,100-foot level. The lower part of the shaft was sunk separately and at a steeper angle of about 60?. The steeper incline was necessitated by downward offset of the Sixteen-to-One vein in the footwall of the "2,100 fault zone" and by steeper dips on the vein below the fault zone. The lower section penetrated the vein at the 2,700-level, and crosscuts were driven to the west and east to drifts on the 2,700- and 3,000-foot levels.

Other Databases

Link to USGS MRDS:	10077649

Other Regions, Features and Areas containing this locality

References