Coin Rescue Inc
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Here is a photo of a 53,100 lb of float copper found in Michigan's UP in 1997 with a metal detector.
Something to think about
This specimen of float copper was discovered in 1997 on the Quincy Mine claims near Hancock, Northern Michigan by the two land holders, Mr. Rudy Kastelic and Mr. James Meneguzzo, while searching their property with a metal detector. As they scoured the forest for metal, they detected a signal indicating a large metal object was buried under their feet. As excavations progressed over the following days, the float copper was finally exposed. It was approximately 14 feet long and 12 feet wide, with thickness up to 17 inches!
In later years, the copper “nugget” was moved from the Quincy Mine claims to the Presque Isle Park in Marquette, Michigan.
The weight of the float copper is estimated at [26.6 tons, or 53,100 pounds (24,085kgs)]. Copper nuggets from the upper Michigan Peninsula generally have a copper purity of 90% to 97%. So, using a purity of only 90% copper by weight, the copper specimen has a current conservative metal value estimate of $101,000! However, this float copper has been declared the world’s largest float copper specimen currently known and it is incredible that it has remained an intact specimen and not been cut and melted into copper wire!
Geologists estimate that the metallic copper formed more than one billion years ago. At that time the earth was still forming crustal land masses and massive amounts of basalt was extruding from the mantle and spreading over large areas of what is now the Michigan, Wisconsin and Minnesota region.
Over several hundred million years, the basalt flows subsided into rift structures that eventually created the Great lakes between the United States and Canada. During this period, hydrothermal fluids rich in copper, silver and other mineral forming ions, were pushed up from deep in the mantle and filled the gas holes that existed in the original basalt flows. Temperature and pressure conditions changed in the trapped fluids and allowed the copper held in solution to form solid copper metal inside the open voids.
Over the following eons of time, ice ages occurred in the northern hemisphere and the ice advances and withdrawals removed thousands of feet of covering sediments from on top of the buried basalt flows. Approximately 12,000 years ago, the last great ice sheet covering North America melted back to the north and dropped from its icy clutches the earth, rocks and large formations of copper nuggets the ice had scraped from the surface. The action of glacial scraping and polishing, as the ice moved the copper nugget across the surface is visible on the float copper. Many of these nuggets remained exposed on the surface of the land, but the larger, pure metal copper masses were usually buried under layers of sand, silt and other debris left by the retreating glaciers. For the area of Northern Michigan, these earth formation processes created and then exposed not only the copper nuggets found on or near the surface, but also valuable deposits of copper that were to be discovered and mined during the past few hundred years.
Nuggets of float copper were often found and used by early inhabitants of the northern Michigan, Wisconsin and Minnesota regions. Copper implements have been found in prehistoric grave sites, excavated in the northern Michigan and Wisconsin areas, dating back to 3000 B.C. Items such as copper spear points, ax heads, knife blades, and decorative ornaments are common in many of the burial sites. Analyses have shown that these early copper implements were “cold-worked” into spear points, arrow heads and other objects, indicating the copper must have come from native copper masses found on the surface. Ancient Indian gravesites of more recent periods, during the past two thousand years, show a progression of working the copper tools and cooking implements from cold hammering of the native copper to eventually using a smelting process to form elaborate copper vessels.
Early non-Indian settlers to the Northern Michigan region in the early 1800’s learned of large masses of float copper from local Indian tribes. Knowledge of easily accessible native copper on the surface drew more and more prospectors to the region looking for copper nuggets and eventually to claiming land to begin larger scale working of underground copper deposits. The late 1800’s and early 1900’s saw a “copper boom” period of exploration, mining and processing of the copper deposits of Northern Michigan. Almost all surface copper nuggets found during this period were sent to the smelters and melted to produce pure copper metal. By the 1960’s the Northern Michigan copper mines were largely exhausted of economical ore and suspended operations. (reprinted from a magazine called Collectors Edge)
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