Unnamed Occurrence (ARDF - TN050; near Ruby Creek), Hot Springs Mining District, Yukon-Koyukuk Census Area, Alaska, USAi

Regional Level Types
Unnamed Occurrence (ARDF - TN050; near Ruby Creek)	- not defined -
Hot Springs Mining District	Mining District
Yukon-Koyukuk Census Area	Census Area
Alaska	State
USA	Country

Location: This site represents a sample of a copper-quartz-gold vein on the ridge northwest of middle Ruby Creek, 4 miles upstream of its confluence with Minook Creek, and 3 miles upstream from the placer workings on Ruby Creek (TN053; Reifenstuhl and others, 1997 [PDF 97-29h]). The site is at an elevation of 2,000 feet, in the northeast quarter of section 32, T. 7 N., R. 13 W., of the Fairbanks Meridian. The location is accurate.
Geology: The ridge between Russian Creek and Ruby Creek is underlain by pelitic schist and subordinate marble and quartzite, in high-angle fault contact with Triassic (Rampart Group) argillite and chert, gabbro, and diverse schists (Chapman and others, 1982; Reifenstuhl and others, 1997 [RI 97-15a]). The area is cut by the northeast-trending Victoria Creek fault zone, a major dextral fault connecting the Tintina and Kaltag faults (Reifenstuhl and others, 1997 [RI 97-15a]). In 1996, the Alaska Division of Geological and Geophysical Surveys sampled a 3-foot wide, quartz breccia zone in quartzite on Ruth Creek ridge, about 3.5 miles upstream from the Ruby Creek (TN053) placer deposit (Liss and others, 1997). The sample (number 96RN191) contained 42 parts per billion gold, 3,678 parts per million (ppm) copper, 8.7 ppm silver, 100 ppm cobalt, and 2.1 ppm tellurium. The breccia zone strikes N50E and is marked by prominent copper staining. White mica (sericite) from a quartz vein in this breccia zone yielded an Ar/Ar isotopic age of 61.2 +/- 0.3 Ma (Reifenstuhl and others, 1997 [PDF 97-29h]). Such veins may be the source of some of the placer gold in Ruby Creek.
Workings: In 1996, the Alaska Division of Geological and Geophysical Surveys sampled a 3-foot wide, quartz breccia zone in quartzite on Ruth Creek ridge, about 3.5 miles upstream from the Ruby Creek (TN053) placer deposit (Liss and others, 1997). The sample (number 96RN191) contained 42 parts per billion gold, 3,678 parts per million (ppm) copper, 8.7 ppm silver, 100 ppm cobalt, and 2.1 ppm tellurium.
Age: White mica (sericite) from a quartz vein in this breccia zone yielded an Ar/Ar isotopic age of 61.2 +/- 0.3 Ma (Reifenstuhl and others, 1997 [PDF 97-29h]).

Commodities (Major) - Au; (Minor) - Ag, Cu
Development Status: None
Deposit Model: Low-sulfide Au-quartz veins(?) (Cox and Singer, 1986; model 36a).

Other Databases

Link to USGS - Alaska:	TN050

Other Regions, Features and Areas containing this locality

References