Information on Traverse City, Michigan and the surrounding Northwest Michigan area

Summer Guide, June 2006

Rocking out

Rock expert Kevin Gauthier explores the bounty of the lakes

by andy taylor-fabe

If you have ever stopped on the beach, picked up a colorful rock and wanted to know more about it than just its color, help is on the way.

The Lake Michigan Rock Picker's Guide is a rock hound's Bible, covering everything from common minerals to semi-precious stones to gold-panning and the elusive diamonds that occasionally show up in the lake.

Photo courtesy of Kevin Gautheir
Diamonds found in Lake Michigan. According to Bruce Mueller of C&M Rock Shop in Beulah, Lake Michigan is one of the largest diamond fields in the U.S.

Kevin Gauthier, the owner of Kormer Gem in Traverse City, co-wrote the book with Bruce Mueller, owner of C&M Rock Shop in Beulah. Mueller wrote the technical aspects of the book, dealing with geology and hard science. Gauthier handled the practical side and the burning question on every rock picker's mind: Where do you find the rocks?

"There's no secret," Gauthier said. "People always lean in and ask where I collect rocks, as if there is some secret special spot. A lot of times, it's gravel pits, rooftops, septic gravel. They're all over."

The book focuses on stones that people are likely to find in the area, including Petoskey stones, corals, horn coral, chain coral, basalts, quartz and granite. Gauthier said Lake Michigan has the most variety of colors of stones in the world.

"In an hour, I went out and picked up stones of every color in the color wheel except true purple," he said. "But that's after 30 years of picking up rocks."

Gauthier's interest in rocks started when he was 14, when he would use a scuba mask to look for rocks in the lake. (Gauthier was featured in the Record-Eagle at the time -- see photo) He joined the Grand Traverse Area Rock and Mineral Club, where he learned much of what he knows. He is still a member of the club.

"I'm pretty much self taught," he said, although he has taken technical classes through the Gem Institute of America.

Brian Lewis of Petoskey Publishing, which is publishing the Rock Picker's Guide, said the book is divided between the geological and historical data about the rocks and more layman-friendly content like tales of impressive finds or information about precious or unusual gemstones or minerals in the area.

Gauthier said that people occasionally find diamonds in Lake Michigan.

"The diamonds were pushed from Canada by glaciers," he said. "More are found on the Milwaukee side."

The book also tells about people panning for gold.

"But those are really rare finds," Gauthier said.

The book also focuses on rocks and minerals that can more easily be found in the area and of impressive finds, like a piece of Lake Superior Agate found south of Leland that weighed 6.5 pounds.

"Leland Blue" is an unusual specimen because it was not formed by nature. It is "slag," blue glass mixed with borox and other chemicals that was waste product from iron foundries in the 1800s. The iron was being smelted for the railroads, and the waste product ended up in the Lake as blue, pourous rock. Gauthier said the interesting thing about Leland Blue is that there's a relatively small amount of it left.

The book also tells people what they can do with stones they collect, from polishing to jewelry to arts & crafts such as cabinet knobs and planters.

Gauthier said he has mixed feelings about rock collecting, since he's dealing with an exhaustible resource.

"There'll always be stones," he said. "But there's a lot of collecting, and there'll be less and less of the unusual stones."

But, he added, "We only borrow rocks. When we pass on, they'll still be here."

"Future generations will have rocks, but the days of finding a five-gallon bucket of Petoskeys are long gone," he said.

Stone collecting is not allowed in federal parks. Check with state park officials about rules for collecting in state parks. Collecting for commercial purposes is not allowed in most places.

The Lake Michigan Rock Picker's Guide will be available in mid-June at local bookstores and at www.petoskeypublishing.com. Kevin Gauthier can be reached at Korner Gem in Traverse City at 929-9175 (GET MAP). Bruce Mueller at C&M Rock Shop in Beulah can be reached at 325-2309 (GET MAP).