Fisherman's Island State Park: Petoskey Stone & Charlevoix Stone Rockhounding in Charlevoix County, Michigan

Updated August 2026

Fisherman's Island State Park is a mapped rockhounding spot in Charlevoix County, Michigan. Reported finds include petoskey stone, charlevoix stone, lake superior agate, yooperlite. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Paid / fee dig
County: Charlevoix County
State: Michigan
Postcode: 49720
Coordinates: 45.30801, -85.31020

Geology at Fisherman's Island State Park

This spot sits on Traverse Group, mapped as limestone that formed roughly 395 to 385 million years ago. Chert and agate nodules typically form inside carbonate rock like this and weather out as tough, waxy lumps in soils and creek beds.

Mapped unit: Traverse Group
Age: 395–385 Ma (Middle Devonian)
Rock types: limestone
Elevation: 610 ft

Geologic mapping via Macrostrat and the underlying state geological survey maps (CC BY 4.0). Bedrock at the surface can vary within a mapped unit.

Best time to visit Fisherman's Island State Park

Best months: April to November. Typical highs run 76°F in midsummer and 29°F in midwinter, with winter lows near 17°F.

Climate normals: NOAA 1991-2020 monthlies, CHARLEVOIX station (2 mi away).

Land & collecting status

Pay-to-dig site

This is a fee-dig location. Hours, prices, and what you can keep vary by operator. Call ahead before driving out.

Public-land rules vary by agency, season, and field office. The RockHoundR app pulls live BLM, USFS, NPS, and tribal overlays so you can see exactly which agency manages the ground at this spot.

Sources & verification

Spot details combine the public RockHoundR location dataset, normalized mineral labels, agency land-status checks in the app, and community submissions. Coordinates are approximate until verified in the field.

State guidance last verified: April 1, 2026

Michigan DNR — Rockhounding rules
Michigan Geological Survey
Isle Royale National Park — Rules
Community submissions reviewed against published agency rules

Found at Fisherman's Island State Park

Each chip opens all spots that produce that material; the encyclopedia link opens the full ID and field guide.

Nearby rockhounding spots

Other rockhounding spots within driving distance of Fisherman's Island State Park.

Fisherman's Island State Park FAQ

Where is Fisherman's Island State Park?+

Fisherman's Island State Park is in Charlevoix County, Michigan, at 45.30801, -85.31020.

What rocks and minerals can you find at Fisherman's Island State Park?+

Fisherman's Island State Park is reported to produce Petoskey Stone, Charlevoix Stone, Lake Superior Agate, Yooperlite.

Is collecting allowed at Fisherman's Island State Park?+

Pay-to-dig site. This is a fee-dig location. Hours, prices, and what you can keep vary by operator. Call ahead before driving out. Always confirm current rules with the managing agency before a trip.

What tools should I bring to Fisherman's Island State Park?+

Most agate and jasper is surface float: bring a spray bottle, a pick or small shovel, and a sturdy bag. Wet stones show their banding and translucence.

When is the best time to visit Fisherman's Island State Park?+

The most comfortable months at Fisherman's Island State Park are April to November.

How do I get to Fisherman's Island State Park?+

Open the directions link to navigate to 45.30801, -85.31020 in Google Maps. Some spots are remote, so check road conditions before driving out.

More rockhounding in Michigan

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Open Fisherman's Island State Park on the map

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