World’s Largest Glacial Float Copper: world record in Marquette, Michigan

October 6, 2022

Marquette, Michigan, United States--The large piece of float copper which was on display in Marquette’s Presque Isle Park was actually quite impressive as it weighed in at 26.6 tons, or 53,100 pounds (24,085kgs) and measured 13 feet x 15 feet, setting the world record for being the World's Largest Glacial Float Copper, according to the WORLD RECORD ACADEMY.

"The Smithsonian Institute has confirmed that this specimen is the largest known piece of glacial float copper in the world. It dwarfs the Ontonagon Boulder (less than 2 tons) which is currently on display at the Smithsonian. This globally unique geologic specimen is valued at $255,000," the broadcast-everywhere.net reports.

"Collector’s Edge Minerals Inc., based in Golden, Colorado, USA and its owner and founder, Mr. Bryan Lees, are honored to display the World’s Largest Float Copper specimen at the 4^th Chenzhou, Hunan, China Gem and Mineral Show!," the collectorsedge.com reports.

Photo above: World’s Largest Glacial Float Copper in Marquette, Michigan. Photo: Marquette County Community Foundation

"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."

"A new piece of float copper weighing more than 400 pounds was installed at Presque Isle along with a plaque in memory of Mr. Rydholm in 2017," the awesomemitten.com reports.

"The weight of the float copper is estimated at 26.6 tons, or 53,100 pounds (24,085kgs), the collectorsedge.com reports.

"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."

Photo above: World’s Largest Glacial Float Copper: world record in Marquette, Michigan. Photo courtesy of collectorsedge.com

"The large piece of float copper (which was) on display in Marquette’s Presque Isle Park is actually quite impressive as it weighs in at 28.2 tons and measures 13 feet x 15 feet," the travelthemitten.com reports.

"This piece was discovered on private land in the Keweenaw Peninsula, and was kept from being melted down thanks to the efforts of late historian and educator Fred Rydholm. Efforts continue to raise the money needed to keep this piece of history on display."

Photo above: World’s Largest Glacial Float Copper: world record in Marquette, Michigan. Photo: Lucy Hough

"A new piece of float copper and plaque were unveiled at Presque Isle in Marquette," the uppermichiganssource.com reports.

"The ceremony started with a brief presentation about the late historian Fred Rydholm.The copper and plaque were dedicated in honor of him.

""It's a tribute to Fred Rydholm, I think it's a nice honor, he has really done a lot for the community as far as making them aware of what the float copper was," said June Rydholm, Fred's Wife. The float copper piece weighs more than 400 pounds. The 28 ton chunk of copper that was at Presque Isle was returned to it's original owner in Calumet, it's currently on display in Bejing, China."