The Importance of the Cliff Discovery
This is the sixth and final post in a series providing an historical context for the Cliff Mine beginning with the creation of the State of Michigan and ending with the discovery of the Cliff vein.
The significance of the findings by Hays, Cheny, et. al. can hardly be understated. Large masses of native, or float, copper had up until this point only ever been found in the Keweenaw at or near the surface. Years earlier, Douglass Houghton, in his geological reports for the state of Michigan, hypothesized the origin of native copper as being within the trap rock that comprised the majority of the peninsula’s geology. Here at the base of the greenstone bluff, Cheny and his German miners provided proof. Without a doubt, native copper in the Keweenaw came from the veins and fissures running throughout the peninsula, often perpendicularly to the trap. They were not all carried there by glacial ice from Isle Royale as others argued.
The discovery renewed interest in the area, and offered hope to the many other mining ventures struggling to keep up operations. Focus turned from searching for copper bearing compounds like those at Copper Harbor, where the Pittsburgh & Boston Mining Co. met with failure, to examining fissures in the hopes that they contained the same large masses as those found at Cliff.
Following the Cliff discovery, fissure mining became the dominant form of mineral exploration in the early years of Keweenaw copper district. Places like Copper Falls, the North American, and the North West (later Delaware), all began as fissure mines, and based their operations of those at the Cliff. Eventually, as mass copper ran out, mines moved on to exploring the copper bearing conglomerate and amygdaloidal belts found running the length of the peninsula. By the end of the 1860’s fissure mining all but ended, and the torch passed from places like the Cliff to Quincy and the Calumet & Hecla Mining Companies, whose mines produced continuously for decades to come.