Prehnite with Copper

Unknown Owner

This is a very fine example for the species from this area. Lustrous green and slightly translucent well crystallized botryoidal prehnite lining a large open pocket with small crystals of native copper. In great condition.The Cliff Mine, located in Keweenaw County, Michigan, was the first successful large scale copper mine in the Keweenaw Peninsula and played a major role in the early development of the region's copper industry. Discovered in the early 1840s, the mine quickly gained attention for its rich deposits of native copper found in fissure veins. The Pittsburgh and Boston Mining Company began operations in 1845, and the mine soon became highly productive, yielding large masses of copper and generating substantial profits. At its peak, the Cliff Mine was one of the leading copper producers in the United States, helping to establish Michigan as a major source of copper. However, by the late 1850s, production declined as the richest portions of the vein were exhausted, and mining operations eventually ceased. Today, the Cliff Mine is recognized as a historically significant site that marked the beginning of large scale copper mining in the Keweenaw Peninsula.