How To Find Petoskey Stones

A Petoskey stone is a fossilized colonial coral — specifically the species Hexagonaria percarinata — that lived in warm, shallow seas covering what is now Michigan roughly 350 million years ago during the Devonian period. When dry, a Petoskey stone looks like unremarkable gray limestone. When wet or polished, however, it reveals a striking pattern of six-sided cells, each with a dark center (the former mouth of the coral polyp) and radiating lines that fan outward like rays of sunlight. This distinctive pattern is what makes them instantly recognizable and highly collectible.

The stones were freed from their bedrock source — the Gravel Point Formation of the Traverse Group — by glaciers during the last ice age. Those glaciers plucked coral fragments from the limestone, tumbled and rounded them, and deposited them across the northwestern and some northeastern portions of Michigan’s Lower Peninsula. Petoskey stones became Michigan’s official state stone in 1965, and hunting for them along the Lake Michigan shoreline is one of the most popular outdoor activities in northern Michigan.

How to Identify a Petoskey Stone

The key to finding Petoskey stones is knowing what to look for. Dry stones blend in with ordinary limestone — light gray to dark gray, smooth, and unremarkable. The hexagonal coral pattern only becomes visible when the stone is wet or polished. This is why the waterline is the best place to search: waves keep the stones wet and the pattern visible. Carry a spray bottle of water to test any suspicious dry stones further up the beach.

Each cell in the pattern has a dark “eye” at the center — the fossilized mouth of the coral polyp — surrounded by lighter lines radiating outward. The cells are tightly packed in a roughly hexagonal arrangement. The closely related Charlevoix stone (Favosite coral) looks similar but has smaller, more tightly packed cells that create a finer honeycomb appearance without the prominent radiating lines. Charlevoix stones are somewhat rarer than Petoskey stones, but both can be found on the same beaches. Regular limestone, bryozoans, and other fossils can sometimes fool beginners, so examine the pattern closely: the six-sided cells with radiating rays are unique to Petoskey stones.

Best Beaches for Finding Petoskey Stones

Petoskey stones are concentrated along the Lake Michigan shoreline from roughly Manistee north through Traverse City, Charlevoix, and Petoskey to Harbor Springs. They also appear on Lake Huron shores near Alpena and occasionally on the Wisconsin side of Lake Michigan. The most productive hunting grounds tend to be rocky or cobbled beaches rather than pure sand beaches. Here are some of the strongest locations, organized by area.

Petoskey and Harbor Springs Area

Petoskey State Park is the most popular hunting spot in the state, with nearly two miles of shoreline on Little Traverse Bay. The park requires a Michigan Recreation Passport for entry. Magnus City Park Beach in downtown Petoskey offers quick waterfront access with about 1,000 feet of searchable beach. The Petoskey breakwall area is another local favorite. For a longer search, the Little Traverse Wheelway bike path runs along the shore for over 26 miles, and wherever you see rocky stretches along the waterline, the chances of finding Petoskey stones are good. If you are exploring this part of Michigan, the area also pairs well with a visit to Petoskey in winter for a completely different experience.

Charlevoix Area

Fisherman’s Island State Park, five miles south of Charlevoix, has five miles of cobbled Lake Michigan shoreline and is one of the best hunting grounds in the region. Mt. McSauba Recreation Area and North Point Nature Preserve on the north side of Charlevoix offer quieter, less-trafficked stretches of rocky beach. Michigan Beach Park in downtown Charlevoix provides easy walk-up access. Barnes County Park at the junction of US-31 and M-88 in Eastport is so popular for stone hunting that it hosts a Petoskey Stone Festival on Memorial Day weekend.

Leelanau Peninsula and Traverse City Area

Leelanau State Park at the tip of the peninsula has a stony shoreline and views of the Grand Traverse Lighthouse. Peterson Park, a small township park west of Northport, features a cobblestone beach below a bluff that is consistently productive. Point Betsie Lighthouse near Frankfort has a small beach that regularly yields good finds. Empire Beach near the village of Empire offers views of the Sleeping Bear Dunes and solid stone hunting — note that Empire Beach is outside the National Lakeshore boundary where collecting is allowed, unlike the adjacent Sleeping Bear Dunes beaches.

Manistee Area

Orchard Beach State Park, north of Manistee, sits on a bluff above Lake Michigan with a stairway down to the beach. While erosion has reduced some beach area in recent years, stones can still be found with effort. This is a good option for hunters exploring the southern end of the Petoskey stone range.

When to Go Hunting

Early spring is widely regarded as the best time to find Petoskey stones. Winter ice on Lake Michigan acts like a bulldozer, churning the lakebed and depositing fresh stones along the shoreline as the ice breaks up. Hunting in March and April — before the summer crowds arrive — gives you the best selection. Going out during or shortly after a storm with strong onshore winds is another productive strategy, as wave action uncovers buried stones and washes new ones ashore. Fall storms can also produce good results. Summer is the most crowded time, and popular beaches near parking areas may already be picked over by midday.

Collecting Rules You Need to Know

Michigan law allows you to collect up to 25 pounds of rocks, minerals, or fossils per person per visit from state-owned land, including state parks and public beaches. If a single stone exceeds 25 pounds, the Michigan DNR has the authority to confiscate it — as happened with a 93-pound Petoskey stone found near Northport in 2015, which was eventually placed on display at the Outdoor Adventure Center in Detroit.

Collecting is prohibited on all National Park Service land, including Sleeping Bear Dunes National Lakeshore, Pictured Rocks National Lakeshore, and Isle Royale National Park. Visitors are welcome to find and admire stones on these beaches, but they must be left where they are found. Fines for removing fossils from NPS land start at $325. State parks require a Michigan Recreation Passport for vehicle entry. Always check specific rules at any beach you plan to hunt, as local regulations can vary. If you are a visitor exploring the broader Michigan vacation scene, the northern Lower Peninsula offers far more than just stone hunting.

What to Bring

Petoskey stone hunting requires minimal gear. The essentials are a spray bottle filled with water (to wet dry stones and reveal the coral pattern), a small mesh bag or bucket for your finds, and comfortable shoes you do not mind getting wet. Rubber boots are useful in early spring when the water is cold. A small garden rake can help turn over stones at the waterline. Sunscreen and a hat are important on exposed beaches.

For hunters willing to go beyond the shoreline, snorkeling gear extends your range 10 to 15 feet offshore where unhunted stones may be sitting on the lake bottom. A wetsuit makes this practical outside of midsummer. Petoskey stones are also found inland — in gravel pits, roadcuts, and freshly plowed agricultural fields — though you must have landowner permission to collect on private property. If you find one Petoskey stone, keep looking in the immediate area: they tend to appear in clusters near Petoskey State Park and other productive beaches.

After the Hunt — Polishing Your Stones

An unpolished Petoskey stone loses its pattern the moment it dries. To make the pattern permanent, you can hand-polish the stone at home using progressively finer grits of wet sandpaper — starting around 220 grit, moving to 400, then 600 — followed by a polishing compound. The process takes patience but produces a beautiful, glossy surface that displays the coral pattern clearly. Lapidary shops in northern Michigan sell polishing kits, and many area retailers in Petoskey, Charlevoix, and Traverse City sell pre-polished stones and Petoskey stone jewelry for visitors who prefer to skip the DIY approach.

Keep an eye out for the rare “Pink Pets” — Petoskey stones with a pink hue caused by iron that permeated the coral during fossilization. These are uncommon and highly prized among collectors. Whether you find a pink rarity or a classic gray specimen, the experience of spotting that distinctive hexagonal pattern emerging from an ordinary-looking beach stone is what makes Petoskey stone hunting one of Michigan’s best fossil hunting traditions.