Rock Garden, Inc

RGI, established in 1994, specializes in Tumbled Copper Nuggets and Glacier Art from Upper Michigan plus a variety of Upper Michigan Mineral specimens.

PHONE or TEXT: 906-280-1697

A massive float copper specimen know as the "906 Nugget" is currently on display at the Keweenaw Agate Shop in Copper Harbor, Michigan.  It is an incredible display and shows the power that the glaciers possessed that formed the Great Lakes. This massive piece of Native Copper was ripped from the mountains of basalt that held it for millenia by the 2 mile thick glacier and it was then rolled and tumbled until all the basalt was removed. The remaining nugget of Glacier Art shows how it was smeared into bedrock and beaten up by the power of the glacier before it laid in its glacial grave for the last 10,000 years. The green and purple oxidation on it is from being untouched in the soil since the glacier receded.  It was found on private property in August of 2023 in Houghton county.  This 9224 pound (4.6 ton) Float Copper specimen is considered to be the most artistic piece ever found.  It is worth the drive to see it!

RGI 2025 EVENT SCHEDULE   (Updated 10-15-24)

Jan 1 thru Feb 10  Quartzsite, AZ    Desert Gardens International Rock and Gem Show We are located in the same spot, F-12, right in the middle of the show.  Open 9am to 5pm daily. We will have a great selection of Glacier Art and of course lots of Nice Nuggets!

Glacier Art (Also know as Upper Michigan Float Copper)

Float Copper refers to a piece of native copper that was carried from its original location by the glaciers that formed the Great Lakes. The host rock was ground up by the action of these glaciers but the native copper remained as an artistic nugget. Native copper as "Float" can be found with metal detectors miles from where it started.  The masses are oxidized purple and green after sitting in the soil since the glacier receded approximately 10,000 years ago. The patina and shape are a form of the Glacier's Artwork.

Upper Michigan Copper Nuggets

Upper Michigan's Copper Country has the purest native copper in the world. Metal detectors are used to locate the copper chunks in the poor rock piles that were overlooked by the miners from many years ago. The chunks are then tumbled in a custom tumbler to remove the host rock (basalt) revealing the unique copper nugget shapes. RGI's copper nuggets are ALL NATURAL with no acid treatment and have not been melted - only tumbled and rinsed with water. These are really Nice Nuggets!


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