Rainy Creek Ridge No. 1

Prospect, Inactive

Commodities and mineralogy

Main commodities Ag; Au
Other commodities As; Pb; Sb; Zn
Ore minerals arsenopyrite; galena; pyrite; sphalerite; stibnite
Gangue minerals quartz; carbonate

Geographic location

Quadrangle map, 1:250,000-scale MM
Quadrangle map, 1:63,360-scale C-2
Latitude 63.5654
Longitude -150.7143
Nearby scientific data Find additional scientific data near this location
Location and accuracy The Rainy Creek Ridge No. 1 prospect is at an elevation of about 3550 feet in a saddle on the ridge between the East Fork of Glen Creek and Spruce Creek. It is in the SE1/4 SE1/4 section 31, T. 15 S., R. 16 W., Fairbanks Meridian. The site corresponds to the location of rock sample 254 of Hawley and Associates (1978), and possibly to location 54 of Bundtzen, Smith, and Tosdal (1976) and 59a of Bundtzen (1981). It is about 0.25 mile south of Thornsberry, McKee, and Salisbury's (1984) occurrence 83, which includes the Rainy Creek Ridge No. 1 and No. 2 claims. The location is accurate within 500 feet of Hawley and Associates' (1978) sample site, but it is uncertain whether it actually coincides with the Rainy Ridge No. 1 claim.

Geologic setting

Geologic description

This deposit appears to be on the trace of a nearly vertical fault(?) contact between Birch Creek Schist and Spruce Creek rocks. The contact crosses the ridge between upper Glen and Spruce Creeks; locally, it is intruded by Tertiary mafic dikes (Hawley and Associates, 1978, fig. 4.1-A(1); Thornsberry, McKee, and Salisbury, 1984, fig. K-2).
The deposit consists of a mineralized quartz-carbonate vein in silicified schist. The vein is 4 to 15 feet thick, and strikes N75-85E. It contains arsenopyrite and pyrite, along with minor amounts of stibnite and galena, and possibly a trace of sphalerite. It can be traced discontinuously along strike for about 2500 feet. The maximum grade of a representative chip sample was 0.01 ounce of gold per ton, 1.79 ounces of silver per ton, 2.53 percent arsenic, 0.42 percent antimony, 0.38 percent lead, and 0.043 percent zinc (Bundtzen, 1981, occurrence 59a).
Geologic map unit (-150.716582335016, 63.5648991106775)
Mineral deposit model Low-sulfide gold-quartz vein (Cox and Singer, 1986; model 36a).
Mineral deposit model number 36a
Age of mineralization The vein is along or subparallel to a fault(?) contact that contains mafic dikes of Eocene age. The deposit is assumed to be Eocene (see record MM091).
Alteration of deposit Silicification.

Production and reserves

Workings or exploration The claim is unpatented and there are no workings.
Indication of production None

Additional comments

The prospect is in Denali National Park and Preserve.