Photograph of a child at the beach in Michigan hunting for Petoskey stones.

Michigan Earth Science Quick Facts

Page snapshot: Michigan State Geologic MapFossil; Rock; Mineral; GemHighest and Lowest Elevations; Places to Visit; and Additional Resources.

Image above: A child hunts for Petoskey stones near Antrim, Michigan. Photograph by "marada" (Flickr; Creative Commons Attribution-NoDervis 2.0 Generic license).

Geologic Map of Michigan

Geologic map of Michigan.

Geologic map of Michigan showing maximum ages of mappable units. Image by Jonathan R. Hendricks for the Earth@Home project developed using QGIS and USGS data (public domain) from Fenneman and Johnson (1946) and Horton et al. (2017).

Michigan State Fossil: American Mastodon

The official state fossil of Michigan is the American mastodon, Mammut americanum.

"Museum on the Move: Tracking the Mastodons" by U-M College of Literature, Science, and the Arts (YouTube).

Michigan State Rock: Petoskey stone

Petoskey stone is fossilized Hexogonaria coral from the Devonian Period.

Photograph of a piece of Petoskey stone from Michigan.

Petoskey stone (Hexagonaria coral) from Michigan; hexagons represent individual corallites. Photograph by James St. John (Flickr; Creative Commons Attribution 2.0 Generic license).

"Why Michigan is Full of Extinct Coral Fossils | Petoskey Stones" by Alexis Dahl (YouTube).

Michigan State Mineral: None

Michigan does not yet have an official state mineral.

Michigan State Gem: Chlorastrolite

Also called Michigan Greenstone, chlorastrolite is a variety of pumpellyite with a distinctive “turtleback” pattern created by its interlocking green crystals. It formed in void spaces in basalt during the Midcontinental Rift event, and, because it is substantially harder than the surrounding igneous rock, it is often found as loose, bean-sized pebbles. It is especially abundant on Michigan’s Isle Royale.


Small pieces of chlorastrolite from Michigan. Photograph by Charles Dawley (Flickr; Creative Commons Attribution-NonCommercial-NoDerivs 2.0 Generic license).

Michigan's Highest and Lowest Elevations

Topographic map of Michigan.

Topographic map of Michigan with physiographic regions and point of highest elevation identified. Topographic data are derived from the Shuttle Radar Topography Mission (SRTM GL3) Global 90m (SRTM_GL3) (Farr, T. G., and M. Kobrick, 2000, Shuttle Radar Topography Mission produces a wealth of data. Eos Trans. AGU, 81:583-583).

Highest Elevation: Mt. Avron

Michigan’s highest point, located on the Upper Peninsula, is Mt. Arvon at 603 meters (1979 feet).

Photograph of the summit of the point of highest elevation in Michigan, Mt. Avron.

Summit of Mt. Avron, the point of highest elevation in Michigan. Photograph by Yinan Chen (Flickr; public domain).

Lowest Elevation: Lake Erie

Lake Erie is 174 meters (571 feet) above sea level, the lowest elevation in Michigan.

Places to Visit

University of Michigan Museum of Natural History

Ann Arbor, Michigan.

Visit website

"Michigan Minds: The New U-M Museum of Natural History" by University of Michigan (YouTube).

Schmaltz Geology Museum and Dinosaur Park

Department of Geological and Environmental Sciences, Western Michigan University, Kalamazoo, Michigan.

Visit website

Petoskey, Michigan

Hunt for Petoskey stones!

Visit website

Additional resources

Map showing the physiographic provinces of the midwestern United States.

Earth@Home resources about Michigan and nearby states:

Earth@Home resources about the Midwest region of the United States: