Clark Mine, Copper Harbor, Keweenaw Co., Michigan, USA
|Latitude & Longitude (WGS84):||47° 26' 45'' North , 87° 51' 37'' West|
|Latitude & Longitude (decimal):||47.44583,-87.86028|
|Other regions containing this locality:||Keweenaw Peninsula, Michigan, USA|
|Köppen climate type:||Dfb : Warm-summer humid continental climate|
An underground copper mine consisting of eight shafts and three adits located southeast of Copper Harbour. The Clark Mining Company was organized in 1853 and worked a small vein of copper. Work was suspended in 1854 and in 1855, the Societe Francoise des Mines des Cuivres Natif du Lac Superior purchased the property. In 1857, the property was again sold to the French Copper Mining Co. and was combined with the Bell Mining Co. Work was sporadic or done under tribute until 1901, when all work ceased. In 1942, the property was deeded to the Calumet & Hecla Consolidated Mining Co.
The mine piles at Clark yield very fine specimens of datolite, prehnite, cuprite, and analcime. The East Vein, about 1 mile north of Clark Mine proper, has also been a favorite for datolite and prehnite.
26 valid minerals.
This geological map and associated information on rock units at or nearby to the coordinates given for this locality is based on relatively small scale geological maps provided by various national Geological Surveys. This does not necessarily represent the complete geology at this locality but it gives a background for the region in which it is found.
Click on geological units on the map for more information. Click here to view full-screen map on Macrostrat.org
1000 - 1200 Ma
|Portage Lake Volcanics|
Age: Stenian (1000 - 1200 Ma)
Stratigraphic Name: Portage Lake Volcanics
Comments: This unit is the same as unit Yp on paper map of Sims (1992). Description is taken from that unit description.
Reference: Horton, J.D., C.A. San Juan, and D.B. Stoeser. The State Geologic Map Compilation (SGMC) geodatabase of the conterminous United States. doi: 10.3133/ds1052. U.S. Geological Survey Data Series 1052.