Crystalline Copper (Dendritic) - Eagle Harbor, Keweenaw, Michigan, USA
Former collection Werner Lieber / Former collection Christian Weise
 
Very rare, dendritic-  crystalline copper with very nice leaf structure and history on matrix. The 3.8 cm tall piece was found in offshore waters off Eagle Harbor on the north shore of the Keweenaw Peninsula on Lake Superior, Michigan. The historical specimen was in the important collection of dr Werner Lieber (https://de.wikipedia.org/wiki/Werner_Lieber) and then in the Chrisitian Weise collection.