Calumet & Hecla 1937 Exploration Shaft, Schoolcraft Township, Houghton County, Michigan, USAi

Regional Level Types
Calumet & Hecla 1937 Exploration Shaft	Exploration Area (Inactive)
Schoolcraft Township	Township
Houghton County	County
Michigan	State
USA	Country

This exploratory shaft was located north and slightly east of the St Louis Mine at the lower contact between the Copper City Flow and the St. Louis Conglomerate near an old railroad grade. The following is a quote from the Calumet & Hecla 1937 annual report:

“At the St. Louis property a vertical shaft about 60 feet deep was sunk and exploration by drifting and crosscutting on a wide mineralized fissure zone which lies chiefly in the hanging wall of the St. Louis Conglomerate. Considerable heavy copper occurs in disconnected shoots in this fissure zone. The underground work was supplemented by 4,394 feet of surface diamond drilling. The erratic distributing of the copper makes it impossible to state, at the present time, whether or not this disclosure may later lead to something of commercial importance. With the advent of winter this exploration was discontinued for the time being.”

The St. Louis Conglomerate lies below the Copper City Flow but above the Keweenaw Fault. It represents the deepest formation that was explored during the mining activity on the Keweenaw Peninsula. It has been subjected to extensive hydrothermal alterations including secondary deposits of copper and calcite. The clasts and rock fragments have been tightly bound together by low grade metamorphism.

Other Regions, Features and Areas containing this locality

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