Hope

Prospect, Active

Commodities and mineralogy

Main commodities Au
Other commodities Ag; Cu
Ore minerals chalcopyrite; pyrite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale JU
Quadrangle map, 1:63,360-scale D-4
Latitude 58.8815
Longitude -135.0996
Nearby scientific data Find additional scientific data near this location
Location and accuracy The Hope prospect is at an elevation of about 2,350 feet, in the Kakuhan Range, 2 miles northeast of Pt. Sherman on Lynn Canal and 1 mile west of Lions Head Mountain. It is approximately 0.2 mile east-southeast of the Ivanhoe Mine in the NE1/4 section 32, T. 34 S., R. 62 E. of the Copper River Meridian. The location is accurate.

Geologic setting

Geologic description

Note: Beginning in the 1990s, this and several old other mines and prospects in the vicinity were consolidated by Coeur-Alaska into a single property (Birak, 2006). They have carried out major new drilling and underground exploration that better defines the mineralization, largely blurs the geologic distinction among the old deposits, and extends the ore bodies greatly. They have developed a coherent modern interpretation of the mineralization as a single deposit which Coeur-Alaska intends to mine as a unit. This deposit is described separately in ARDF as the Kensington (Coeur-Alaska) deposit (JU261). For geologic reference purposes and for their historic value, the pre-Coeur-Alaska data for this and the other old mines and prospects that Coeur-Alaska consolidated are retained in ARDF.
The Hope prospect was discovered in 1895 and by 1902 was developed by 2 adits and an open cut. The prospect is an east-trending quartz vein in metamorphosed basalt, unlike most other veins in the Berners Bay district which typically are hosted in Jualin Diorite. The vein is 8 feet thick in one adit. Samples contained up to 25 ppm gold (Redman and others, 1989).
The Hope prospect is in the Berners Bay district at the north end of the Juneau Gold Belt. The district is characterized by a series of structurally-controlled mesothermal, gold-bearing quartz veins. Most of the veins are in Lower Cretaceous Jualin Diorite, which intrudes Upper Triassic metabasalt (Miller and others, 1995). The age of mineralization in the Berners Bay area is about 55 Ma, the same as the other mesothermal gold vein deposits in the Juneau Gold Belt (Goldfarb and others, 1997).
Geologic map unit (-135.101420941599, 58.881169485245)
Mineral deposit model Low-sulfide Au-quartz vein (Cox and Singer, 1986; model 36a).
Mineral deposit model number 36a
Age of mineralization The age of mineralization in the Berners Bay district is about 55 Ma, the same as the other mesothermal gold-quartz-vein deposits in the Juneau Gold Belt (Goldfarb and others, 1997).

Production and reserves

Workings or exploration The Hope prospect was discovered in 1895 and by 1902 it had 2 adits and an open cut.
Indication of production None

References

References

Birak, D.J., 2006, Kensington gold project technical report: Unpublished Technical Report by Coeur d'Alene Mines, 116 p. (posted on www.sedar.com, April 20, 2008 ).
Goldfarb, R.J., Miller, L.D., Leach, D.L., and Snee, L.W, 1997, Gold deposits in metamorphic rocks in Alaska, in Goldfarb, R.J., and Miller, L.D., eds., Mineral Deposits of Alaska: Economic Geology Monograph 9, p. 151-190.
Miller, L.D., Goldfarb, R.J., Snee, L.W., Gent, C.A., and Kirkham, R.A., 1995, Structural geology, age, and mechanisms of gold vein formation at the Kensington and Jualin deposits, Berners Bay district, southeast Alaska: Economic Geology, v. 90, p. 343-368.
Reporters J.C. Barnett and L.D. Miller (Juneau, Alaska ); D.J. Grybeck (Port Ludlow, WA)
Last report date 6/5/2008