Texas Creek Comstock

Prospect, Inactive

Alternative names

Hyder Lead
Texas Comstock
Joe Joe
Fortuna
Alaska-Comstock
Jackson-Hummel

Commodities and mineralogy

Main commodities Ag; Au; Cu; Mo; Pb; Zn
Other commodities Barite
Ore minerals chalcopyrite; galena; molybdenite; pyrite; pyrrhotite; sphalerite; tetrahedrite
Gangue minerals quartz; calcite; chlorite

Geographic location

Quadrangle map, 1:250,000-scale BC
Quadrangle map, 1:63,360-scale A-1
Latitude 56.042
Longitude -130.256
Nearby scientific data Find additional scientific data near this location
Location and accuracy The above coordinates are for the approximate center of a group of five prospects in a map area about 0.5 mile (Lat 56.039-56.044) by 1.0 mile (Long 130.246-130.265) on the mountainside south of Texas Lake (Elliott and Koch, 1981, p. 13, loc. 37). The prospects are at elevations ranging from about 3200 to 4300 feet in Sections 21 and 22. The location of the prospect area is probably accurate within about a quarter of a mile.

Geologic setting

Geologic description

The country rocks in the general area of these prospects include pelitic metasedimentary and subordinate andesitic metavolcanic strata of the Jurassic or older Mezozoic Hazelton Group; the Triassic Texas Creek Granodiorite, which underlies and locally intrudes the Hazelton; and the Eocene Hyder Quartz Monzonite, which intrudes both the Hazelton and Texas Creek rocks (Smith, 1977; Koch, 1996).
Buddington (1925, p. 91-93; Cobb, 1978, p. 42-43) described a deposit, called 'Texas Creek Comstock' in his report, as quartz fissure veins up to 11 feet thick in granodiorite, metamorphosed graywacke, and tuff that contain galena, pyrite, chalcopyrite, and molybdenite. Andesite porphyry and aplite dikes cut both the granodiorite and metamorphic rocks. Assays showed 3.6-16.9 oz Ag and a trace to 0.18 oz Au per ton, and as much as 0.61 percent Cu, 72.8 percent Pb, and 2.6 percent Zn.
In 1929, Buddington (1929, p. 102-108) described quartz veins in quartz diorite of the Texas Creek Granodiorite and in the metagraywacke and tuff in the roof of the pluton. The veins in the pluton generally are leaner in metallic minerals than those in the overlying bedded rocks. The veins carry galena, pyrite, chalcopyrite, sphalerite, pyrrhotite, and tetrahedrite. Gangue minerals include quartz, barite, calcite, and chlorite. Free gold was found in a piece of quartz (?) float from an unknown source.
Lead-isotope studies of galena from the Hyder Lead prospect (Maas and others, 1995, p. 229-248) indicate that the deposit is Eocene in age, contemporaneous with emplacement of the Hyder Quartz Monzonite.
Geologic map unit (-130.257705269894, 56.0416894753003)
Mineral deposit model Polymetallic veins (Cox and Singer, 1986; model 22c).
Mineral deposit model number 22c
Age of mineralization Lead-isotope studies of galena from the Hyder Lead prospect (Maas and others, 1995, p. 229-248) indicate that the deposit is Eocene in age, contemporaneous with emplacement of the Hyder Quartz Monzonite.

Production and reserves

Workings or exploration
Early workings included surface stripping and opencuts.
Early assays showed 3.6-16.9 oz Ag and a trace to 0.18 oz Au per ton, and as much as 0.61 percent Cu, 72.8 percent Pb, and 2.6 percent Zn.
Indication of production None

References