Rock Garden, Inc

RGI, established in 1994, specializes in Tumbled Copper Nuggets and Glacier Art Copper 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 3-1-25)

Aug 2   Ishpeming, MI    Ishpeming Rock and Mineral Club Annual Gem & Mineral Show  - Located at the Elks Club.  We have an outside booth again this year and will have a huge variety of great rocks and minerals.  This is always a fantastic 1 day only show!  9:00AM to 3:30PM

RGI 2026 EVENT SCHEDULE  

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. As always, we will have a great selection of Glacier Art Copper and of course lots of Nice Nuggets!

Glacier Art is a Registered Trademark #803297111

Glacier Art 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 (Cuprite and Malachite) 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. The high spots of these pieces are then polished to show the inner beauty of the copper.

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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