Species: Native Copper, Malachite, Andularia
Locality: Adventure Mine (2nd Level), Greenland, Ontonagon County, Michigan USA.
Dimensions: 10.5 x 8 x 4.5 cm.
The Adventure mine, whose operation dates back to the mid 19th century, is currently enjoying a renaissance as a “tourist mine” which offers a combination of underground mine tours along with other activities such as rappelling, mountain biking, and mineral collecting. Over the past ~5 years, local mineral collector and miner Bob Barron has partnered with the owners of the Adventure mine to mine and prospect for mineral specimens on the recently de-watered second level of the mine. This excellent, quite unusual specimen of large, blocky dodecahedral copper crystals to ~2.5 cm coated with malachite on andularia matrix was collected by Barron in the summer of 2017, in a small pocket he found by drilling and blasting the Knowlton Copper orebody. Specimens of blocky copper crystals on crystallized andularia matrix are quite unusual overall from the Michigan Copper Country, but the vibrant green malachite coating on the copper really adds an extra aesthetic element and makes this a fine example of copper from a historically-important mine. Annette Slade photo.