William Henry

Prospect, Inactive

Commodities and mineralogy

Main commodities Cu; Pb; Zn
Other commodities Au; REE
Ore minerals barite; galena; molybdenite; pyrite
Gangue minerals calcite; feldspar

Geographic location

Quadrangle map, 1:250,000-scale JU
Quadrangle map, 1:63,360-scale C-4
Latitude 58.7446
Longitude -135.2904
Nearby scientific data Find additional scientific data near this location
Location and accuracy The William Henry prospect is at an elevation of about 3,300 feet, on the west flank of William Henry Mountain and 2 miles west of Lynn Canal. It is located in the SW1/4 section 17, T. 36 S., R. 61 E. of the Copper River Meridian. The location is accurate within 1/4 mile.

Geologic setting

Geologic description

The general area is underlain mainly by Silurian and Devonian graywacke and argillite and Middle Devonian carbonate, clastic and volcanic rocks (MacKevett and others, 1971; Brew and others, 1978). The country rocks at this prospect are Silurian graywacke and Devonian and Silurian greenstone intruded by small bodies of Cretaceous quartz monzonite and syenite (Clough and Redman, 1989). The quartz monzonite, which contains feldspars crystals up to 4 inches long, contains disseminated pyrite, and is highly altered to sericite, chlorite, epidote and clay minerals. The sedimentary and volcanic country rocks are silicified and contain disseminated pyrite. Carbonatite forms northwest-trending veins up to a foot thick. They are composed mostly of calcite and minor feldspar phenocrysts. The veins carry variable amounts of pyrite, galena, molybdenite, barite, rutile and biotite. Analyses of the veins show small amounts of rare-earth elements and elevated values of copper, zinc and gold. The area has been explored for uranium-thorium minerals (Clough and Redman, 1989).
Geologic map unit (-135.292218764749, 58.7442698879766)
Alteration of deposit Pyrite-sericite-chlorite-epidote-clay alteration in quartz monzonite; silicification and pyritization of sedimentary and volcanic country rocks.

Production and reserves

Workings or exploration Surface sampling and mapping.
Indication of production None

Additional comments

The Lucky Six (JU057) , William Henry (JU060), Kings View (JU058), Athero (JU062), and an unnamed occurrence (JU059) are on the flanks of William Henry Mountain and have been collectively referred to as the William Henry prospect or as being in the William Henry area.

References