Michigan’s State Stone – Fossil Coral called Petoskey Stones and YOU can find one!

Unpolished Petoskey Stone with cm scale - photo by David J. Fred CC

Unpolished Petoskey Stone with cm scale – photo by David J. Fred CC

Take the Petoskey Stone. Don’t worry, hundreds of thousands of these stones have been picked up from the beaches, fields, quarries and roadsides near Michigan’s Traverse Bay. Local tourism welcomes you to take a few home with you fromTraverse City and upwards through the towns of Ames, Elk Rapids, Torch Lake, and up to Charlevoix, where many suggest visiting the beaches in order to find these stone fossils. These stone replaced corals are abundant and often take a fine polish, used for tumbling, cabbing and slabbing. The floral patterns and semi-hard, easy to polish, calcite replacement make this a stone that was sure to bring rock collectors of all walks of life to this area of the world.

This vast area of Michigan was once covered by an ocean full of corals, the Hexagonaria percarinata, among others, which at some point in time were covered up with rock, turning into vast limestone deposits with countless bits of these dead corals well preserved, from millions of years ago. Bring the glaciers into the picture and suddenly the stone corpses of these corals are spread out all over the state, wherever the glacier dragged chunks of this limestone about. People have experienced finding these Petoskey stones all over the state, however, the most popular locations for collecting are on the shores of Lake Michigan, as the frost and rain pushes and pulls the sands and gravels, revealing more each year.

Hexagonaria percarinata close view  - photo by Wilson44691

Hexagonaria percarinata close view – photo by Wilson44691

This rock collecting area is all about exploring. You can find hot spots where the specimens seem to crop up everywhere, you can walk for a half mile and not see a one. Anywhere there is gravel, that is a great place to hunt. There is a world of information about these stones, so many websites, books, articles, parks, dedicated to these funky fossils. This year it was all about the 90ish pound boulder specimen pulled out of Lake Michigan. I personally saw the photo pop up on instagram, then get taken down. The state has a limit of 25 pounds collected at a time! There is a photo of President Obama with one of these stones on his desk. It is the state stone of Michigan and certainly a draw for tourism. So, I highly suggest grabbing a copy of this book, The Complete Guide to Petoskey Stones

Check out the following links below for more information on Petoskey stones and click here or on the banner below to check out Petoskey Stones available for sale on eBay.
The Petoskey Chamber of Commerce has a great website detailing information about Petoskey Stones and where they can be found and purchased, locally, in Michigan!
You can check out our friends at RockTumbler.com for information on tumbling, polishing and grinding your specimen of Petoskey Stone. That site has great information.
Here is an article about Obama’s very own pet Petoskey Stone
Here is an article about the Petoskey Stone that cause the big news in 2015.

Photo of a  polished Petoskey Stone, Hexagonaria percarinata

Photo of a polished Petoskey Stone, Hexagonaria percarinata – Photo CC

The best thing about hunting Petoskey Stones is the beauty that is Upper Michigan. The beach views of Lake Michigan are said to be breathtaking, the landscape is full of greenery and wild flowers in the spring.

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Collecting Copper in Michigan’s Copper Country

Field Trip: Copper Country Collecting in Michigan’s Keweenaw Peninsula

By Jeremy Zolan

Difficulty Level: Easy to Moderate

Supplies Needed:
Safety Goggles
Insect Repellant
Crack Hammer
Wrapping Paper for Specimens
Sledgehammer (optional)
Prybar (optional)
Metal Detector (optional)


The Keweenaw Peninsula of Michigan has been nationally famous for over 100 years for its history of highly productive copper mining. The local basalt is criss-crossed with many thick veins of native copper that made up the main ore of many of the mines. Solid natural masses of copper weighing hundreds of pounds were found with relative frequency at the mines. Though these pieces certainly were the most valuable ore, the best specimens from the area are clusters of well formed copper crystals. Other metallic minerals can be found with the native copper such as silver, domeykite, mohawkite, and chalcocite. Many other interesting minerals like datolite, analcime, prehnite, agate, and thomsonite are also abundant in the Keweenaw Peninsula. While all the mines of the region are closed to copper production, many are maintained as museums and fee dig sites. There are also many abandoned mines in the area that can provide good digging in the dumps but be sure to acquire permission from landowners before visiting any location on private land.


Central Mine:
US 41
Central, MI 49950

Photo by Dave Maietta


The large tailings piles of the Central Mine are visible from US 41 in Central, Michigan. Many collectors have had good luck recently working this location. Occasionally, contractors remove large quantities of tailings for construction purposes and this exposes fresh material. In addition to the standard copper specimens, copper included calcite and prehnite can be found here. Silver has also been found with copper here but it is rare. A metal detector is very helpful for sorting trough dump piles like those found at the Central Mine.

Caption: Calcite with copper inclusions. Central Mine, Central, MI 4.9 cm x 4.6 cm x 4 cm Ex. Rukin Jelks Rob Lavinsky Photo

Caption: Unusually large copper crystal. Central Mine, Central, MI. George Vaux collection at Bryn Mawr College. Scale bar is 1” long with rule at 1cm. Rock Currier Photo.central_mine_copper

Caledonia Mine:
Website: http://www.caledoniamine.com/
202 Ontonagon St,
Michigan 49953

The Caledonia Mine is a fee dig site that requires an advance reservation. When digging at this site, collectors are given a large pile of stockpiled copper ore and tools to go through it. Weekly collecting events on Thursdays and Saturdays are also held from the first Thursday in June to the last Saturday in August on the ore pile. Advance reservations are needed for these too. The workings of the Caledonia Mine are impressively preserved and tours are offered too. The mine tours aren’t necessarily just geared for casual guests. Many kinds of tours are offered, some with a very in depth historical or scientific focus. It is best to check the museum calendar to see if any events are happening during the time of your visit.

Caption: Representative specimen of native copper from the Caledonia Mine’s recent workings. 5.6cm wide. Rob Lavinsky Photo

A.E. Seaman Mineral Museum
Website: http://www.museum.mtu.edu/
Michigan Technological University
1404 E. Sharon Avenue
Houghton, Michigan 49931-1295
E-mail: tjb@mtu.edu
Telephone: (906) 487-2572

Michigan Tech’s A.E. Seaman Mineral museum is among the finest mineralogical museums in the world. Its laboratories are also critical in performing much of the cutting edge mineral research currently being performed. During the period of most intense copper mining in Michigan, many specimens of local minerals were donated to the museum. Their collection of Michigan minerals is the finest in the world and there is a strong local emphasis on their displays.

Check out our custom search and view all the minerals from Michigan for sale on eBay. Not only will you see lots of neat stuff for sale, you’ll also get an idea of what localities are producing in the region.

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