|Location:||Mass, near Hubbell, Ontonagon County, MI|
|Open:||By appointment. During the Copper Country Mineral Retreat. |
Red Metal Minerals, P.O. Box 445, 75 Hwy M-26, Hubbell, MI 49934, Tel: +1-906-296-9440, Fax: +1-906-296-1055.
Richard Whiteman, E-mail:
|As far as we know this information was accurate when it was published (see years in brackets), but may have changed since then.
Please check rates and details directly with the companies in question if you need more recent info.
|1870||fire destroyed the mill.|
|1870||Caledonia Mine combined with the Flintsteel properties.|
|1873||leased by Captain Martin and reopened.|
|1937||reopened by Calumet and Hecla Consolidated Copper Company.|
|1939||closed because of World War II.|
|1950||test mining by Calumet and Hecla Consolidated Copper Company.|
|1971||evaluation of the mine by Copper Range Company and the U.S. Bureau of mines.|
|1972||plans for insitu leaching dropped due to potential problems of groundwater pollution.|
|1985||mineral rights acquired by Red Metal Explorations.|
The Mass area is covered by basalt lava flows which dip about 45 degrees northwest towards Lake Superior. Some of the flow tops, especially of the Evergreen Series, are mineralized with copper. They are fragmental amygdaloids, breccias, with abundant minerals fillings in the amygdules and between fragments. Abundant minerals are quartz, feldspar, pumpellyite, chlorite, calcite and epidote. Less abundant are native silver, prehnite, datolite and laumontite.
The deposits are stratabound, but due to the dip mined underground. The two stratigraphically highest deposits are Butler and Knowlton lode, which were the center of the mining. But there were also adits to South Knowlton, and Mass lodes.
Caledonia Copper Mine once consisted of two shafts, each 60 m deep. One 90 m long adit was driven into the Butler lode, four into a mineralized cross vein. The Caledonia Mine has yielded about 3.1 million kg of refined copper since it was opened in 1863. From 1863 to 1870 410,000kg of refined copper were mined at a grade of about 1.25% copper. 1873 to 1881 more than 150,000 kg of copper was removed. 1951 to 1958 2.521 million kg of refined copper was produced at an average grade of 1.24% copper.
A specialty of this mine is the abundance of minerals including native copper and silver. Even huge pieces of copper wer found. Captain Martin removed a single mass weighing 36,000kg in the 1870s. Red Metal Explorations, who owns the mine today, reopened the No. 4 Caledonia adit is mining specimens. The largest single piece they removed to date weighed 1360kg.
Caledonia Mine is primarly the source of the stock of Red Metal Explorations, and as such a working mine. There are regular possibilities to visit the mine during the Copper Country Mineral Retreat, a one week mineral collecting event held once a year by the A.E. Seaman Mineral Museum, Michigan Technological University.