Indian; Blue Ridge Prospect, Chistochina Mining District, Valdez-Cordova Census Area, Alaska, USAi

Regional Level Types
Indian; Blue Ridge Prospect	Prospect
Chistochina Mining District	Mining District
Valdez-Cordova Census Area	Census Area
Alaska	State
USA	Country

Additional information can be obtained from Ahtna Minerals in Anchorage, Alaska.
Location: The Indian or Blue Ridge prospect is about one mile northwest of the west end of Long Lake at an elevation of about 5,100 feet. The coordinates are the site of a vein exposed on the ridge; it is at the center of a mineralized area which is mainly in the SE1/4, section 14, T. 12 N., R. 6 E., Copper River Meridian. The prospect is at locality 5 of Richter and Matson (1972), and locality 5 of MacKevett and Holloway (1977).
Geology: The Indian prospect is mainly in relatively coarse and dark-colored, quartz monzonite of the Pennsylvanian to Permian, Ahtell pluton. It lies within a few hundred feet of its contact with Pennsylvanian to Permian, Tetelna volcanic rocks which are exposed to the south. The contact between the two units is a fault which strikes northwest. The fault zone is filled with a barren quartz vein that can be followed for more than 1,000 feet (Richter, 1966, p. 30; Thorne, 1946, fig. 2). The area was first described by Moffit (1932) who visited the area in 1929. The prospect was restaked by Carl Witham and was examined by Thorne of the U. S. Bureau of Mines (Thorne, 1946) in company with Witham. Thorne made a sketch map of the property. Their map (figure 2) is the best available for the property. In addition to the barren quartz vein, Thorne found five other veins. Thorne (1946, table 1) collected three samples from an east-west striking vein on the Blue Ridge No. 2 claim. This vein is exposed in pits on the west side of the ridge and about 150 feet north of the fault contact of the Ahtell pluton and Tetelna volcanics. Sample 1 from a 2-foot-thick vein that contains galena, chalcopyrite, tetrahedrite, and secondary azurite and malachite in quartz-calcite gangue, assayed 0.01 ounce of gold per ton, 11.44 ounces of silver per ton, 4.18 percent lead, and 1.44 percent copper. Thorne's sample 2 was low grade, partly because of dilution with barren soil. Sample 3 of a 1-foot vein contained 5.16 ounces of silver per ton, 6.81 percent lead, and some copper. The veins are crustified and the sulfides fill open spaces in the crystalline quartz. A narrow vein exposed about 4000 feet to the east of the barren quartz vein on the Blue Ridge No. 5 claim contained 0.04 ounce of gold per ton, 15.56 ounces of silver per ton, and 19.92 percent lead. Another vein exposed on the ridge on the end line between the Blue Ridge Nos. 5 and 1 claims contains 5.24 percent lead and small amounts of gold and silver. The area was visited later by Richter (1966) but the trenches excavated by Witham and Thorne were caved. One vein that remained exposed was 5 feet thick, has a strike of N84W and dips 86 degrees south. It is mainly massive quartz with some galena and copper-staining. Wedow and others (1953) and Nelson, West, and Matzko (1954) found no appreciable uranium in the veins.
Workings: The area was active when visited by Moffit in 1929 (Moffit, 1932). The prospect was again active late in World War II when it was examined by Thorne (1946) with the then-current owner, Carl Witham. The only workings are hand-dug open cuts.
Age: Emplaced subseqent to or is related to the border phase of the Pennsylvanian to Permian, Ahtell pluton.

Commodities (Major) - Ag, Au, Cu, Pb
Development Status: None
Deposit Model: Polymetallic vein(?) (Cox and Singer, 1986; model 17)

Other Databases

Link to USGS - Alaska:	GU026

Other Regions, Features and Areas containing this locality

References