Dividend

Prospect, Inactive

Commodities and mineralogy

Main commodities Au
Other commodities Pb
Ore minerals arsenopyrite; galena; native gold; pyrite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale JU
Quadrangle map, 1:63,360-scale C-3
Latitude 58.5846
Longitude -134.804
Nearby scientific data Find additional scientific data near this location
Location and accuracy The Dividend prospect is at an elevation of about 1,300 feet, on the southeast wall of Yankee Basin. It is in the NE1/4NW1/4 section 14, T. 38 S., R. 64 E. of the Copper River Meridian. The location is accurate within 1/4 mile.

Geologic setting

Geologic description

The Dividend prospect is in northwest-trending, intercalated black phyllite and greenstone (Redman and others, 1989). The deposit consists of discontinuous quartz lenses and quartz-stringer veins in sheared black phyllite. The quartz contains arsenopyrite, galena, pyrite, and native gold. The stringer zones are up to 10 feet thick, and the stringers vary from 1 inch to 1 foot thick. U.S. Bureau of Mines samples contained up to 6.4 ppm gold (Redman and others, 1989). The prospect area was explored by Houston Oil and Minerals in 1985. The deposit was discovered in 1903 and developed by the so-called Standard crosscut, a 1,100-foot adit (that was reopened by Houston Oil and Minerals in 1985), another short crosscut, 2 shafts, and some trenches (Redman and others, 1989).
This prospect is in the Juneau Gold Belt, which consists of more than 200 gold-quartz-vein deposits that have produced nearly 7 million ounces of gold. These gold-bearing mesothermal quartz vein systems form a zone 160 km long by 5 to 8 km wide along the western margin of the Coast Mountains. The vein systems are in or near shear zones adjacent to west-verging, mid-Cretaceous thrust faults. The veins are hosted by diverse, variably metamorphosed, sedimentary, volcanic, and intrusive rocks. From the Coast Mountains batholith westward, the host rocks include mixed metasedimentary and metavolcanic sequences of Carboniferous and older, Permian and Triassic, and Jurassic-Cretaceous age. The sequences are juxtaposed along mid-Cretaceous thrust faults (Miller and others, 1994). The sequences are intruded by mid-Cretaceous to middle Eocene plutons, mainly diorite, tonalite, granodiorite, quartz monzonite, and granite. Sheetlike tonalite plutons emplaced just east of the Juneau Gold Belt and undeformed granite and granodiorite bodies that are emplaced farther to the east are between 55 and 48 Ma (Gehrels and others, 1991). The structural grain of the belt is defined by northwest-striking, moderately to steeply northeast-dipping, penetrative foliation that developed between Cretaceous and Eocene time (Miller and others, 1994). The majority of the veins in the Juneau Gold Belt strike northwest. Isotopic dates indicate that the auriferous veins in the Juneau Gold Belt formed between 56 and 55 Ma (Miller and others, 1994; Goldfarb and others, 1997).
Geologic map unit (-134.805790862594, 58.5842752579359)
Mineral deposit model Low-sulfide Au-quartz vein (Cox and Singer, 1986; model 36a)
Mineral deposit model number 36a
Age of mineralization Isotopic dates indicate that the auriferous veins in the Juneau Gold Belt formed between 56 and 55 Ma (Miller and others, 1994; Goldfarb and others, 1997).

Production and reserves

Workings or exploration The prospect was explored by Houston Oil and Minerals in 1985. The deposit was discovered in 1903 and developed by the so-called Standard crosscut, an 1,100-foot adit (that was reopened by Houston Oil and Minerals in 1985), another short crosscut, 2 shafts, and some trenches (Redman and others, 1989).
Indication of production None

References

MRDS Number A012071

References

Gehrels, G.E., McClelland, W.C., Samson, S.D., and Patchett, P.J., 1991, U-Pb geochronology of detrital zircons from a continental margin assemblage in the northern Coast Mountains, southeastern Alaska: Canadian Journal of Earth Sciences, v. 28, no. 8, p.1285-1300.
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., Gehrels, G,E., and Snee, L.W., 1994, Genetic links among fluid cycling, vein formation, regional deformation, and plutonism in the Juneau gold belt, southeastern Alaska: Geology, v. 22, p. 203-206.
Reporters J.C. Barnett and L.D. Miller (Juneau, Alaska )
Last report date 12/15/2001