Types of Rocks In Lake Huron: 10 Common Collectible Rocks and Fossils You Can Find

Lake Huron has almost 3,200 miles of shoreline that is filled with fossils and rocks rich in history.

This makes Lake Huron a prime location for rock hunting.

But what rocks can you find there?

Below is a list of 10 common rocks and fossils you can find at Lake Huron.  

Types of Rocks In Lake Huron


The information provided in this article by YesDirt.com is for informational purposes and is subject to change. Laws are updated. Accessibility guidelines and restrictions change. Be sure to confirm the land status and collection rules before you travel to an unfamiliar location or collect any material.

1. Puddingstone

Resembling a Christmas pudding, puddingstones are aggregates brought to the area by glaciers.

The stone itself contains various other smaller stones, such as  black chert, white quartzite, and red jasper, which gives the rock that iconic Christmas pudding appearance. 

They range in size from as small as a pebble to as large as a dump truck, or even larger!

Puddingstones can be found on the shores of Drummond Island, as well as in its forests. Drummond Island is located at the northern end of Lake Huron.

Puddlingstons are often collected for their colorful appearance.

Some people use them as garden decorations, while others make knicknacks and jewelry with them.

2. Lake Superior Agate

These stunning rocks often have bands of creams, reds, oranges, and whites.

They were created by cooling lava about a billion years ago. In fact, this rock is Minnesota’s state gemstone.

The agate gets its color from oxidation of iron, and the amount of iron and oxidation is what determines the color of its bands. 

As their name suggests, the ideal location to find these rocks is on the shores of Lake Superior.

Since Lake Superior drains into Lake Huron via St. Mary’s River, these rocks can sometimes be found in that area as well. 

Agates are resilient stones, and have a long history of use in workshops and laboratories.

Nowadays, most people seek out these stunning rocks to add to their collection or display in their home. 

3. Petoskey Stone

These much sought after stones have unique properties that can sometimes be masked by their pebble-like shape.

Petoskey stones are a fossil rock made from the coral Hexagonaria percarinata.

It is thought that these corals lived during a time before the dinosaurs, when the Lake Huron area was covered by sea.

The stone itself is covered in six-sided coralites that are enhanced when wet or polished.

When dry, however, the stone resembles limestone.

Petoskey Stones can be found on various inland locations and beaches in Michigan.

Experts say that the ideal time to find these stones is in early spring after ice on the Grand Traverse Bay has melted along the shore.

4. Granite

Granite is a popular stone that has long been used to create works of art and even kitchen countertops.

These light-colored stones are comprised of feldspars, quartz, amphiboles, mica, and various other minerals.

This mineral composition causes the stone to have a gray, red, white, or pine hue speckled with black grains.

Granite can be found in various sizes along the beaches of Lake Huron.

5. Charlevoix Stone

This stone looks similar to the Petoskey stone, though it is typically smaller in size, and its pattern has a more honeycomb-like appearance.

Like the Petoskey stone, Charlevoix is made up of the fosselized coral Hexagonaria percarinata. 

These stones can be found scattered along the shores of Michigan’s lower peninsula.

The Charlevoix stone is said to help promote clarity and inner wisdom, as well as give off self-healing energy. 

6. Chlorastrolite (Greenstone)

Known as greenstone, Chlorastrolite is made up of the mineral pumpellyite.

It has a vivid green or blush-green color and a turtleshell-like pattern. 

This stone was named Michigan’s office gemstone in 1973, and it is exclusively found in the Isle Royale archipelago, which is a National Park, and along the Keweenaw Peninsula.

They are much sought after due to their stunning appearance, and are commonly used in jewelry. 

7. Favosite

These stones are made from tightly packed corallites, which gives the rock a honeycomb pattern.

While it does resemble Petoskey in some ways, the openings of the Favosite’s coral polyps are smaller with a pattern that looks more like a lace draping over the stone.

Some people with metaphysical beliefs state that Favosite will bring accomplishments to businesses, while also adding excellence to your life and surroundings.

Favosite is often found in the same areas as Petoskey and Charlevoix stones. 

8. Crinoids

These unusual stones are actually fossils of a marine animal that is related to a starfish but looks like a flower.

The stone itself is small and disc shaped with a hole in the center (think of a Cheerio.)

These discs can be staked on top of one another in varying amounts.

You may also hear this stone called “Indian Bead”, which is a common name used by some in the area.

This is because the Native Americans would use them to make necklaces.

9. Basalt

Basalt stones are often grey to dark grey in color, but may turn a brown or rust color due to the oxidation of iron.

Basalt is commonly used for groundwork or building blocks in construction. It is also used to make statues and cobblestones.

There are a few different types of basalts that can be found in Lake Huron, such as Vesicular Basalt.

This type of basalt resembles traditional basalt but with deep pits. If the pits cover over half of the stone’s surface, it is then called scoria.

10. Brown Septarian Stones

Brown Septarian stones are typically brown in color and are made up of clay and mud that formed along the ocean floor 50 million years ago.

These stones have a unique turtleshell-like pattern that is caused when the rock cracks and is then filled with calcite. 

Septarian stones are believed to be healing and protective stones that help to ground the person who is wearing them, while also bringing happiness and understanding.

Some also believe it is a speaking stone that helps to improve the wearer’s communication skills.


Lake Huron is a wonderful location to spend the day rock hunting.

However, it is illegal to remove more than 25 pounds of minerals or rocks from the Great Lakes.

This is an annual limit, and violators of this law could face civil fines of up to $500.

For private property, there are no limits on how much rock you can collect, but you will need permission from the property owner.

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Types of Rocks In Lake Huron