Old Mission State Park: Rockhounding in Grand Traverse County, Michigan

Updated August 2026

Old Mission State Park is a mapped rockhounding spot in Grand Traverse County, Michigan. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Public area
County: Grand Traverse County
State: Michigan
Postcode: 49673
Coordinates: 44.98999, -85.48987

Geology at Old Mission State Park

This spot sits on Antrim Shale, mapped as black shale that formed roughly 385 to 360 million years ago. Sedimentary rock like this erodes unevenly, so the most productive collecting is typically along fresh cuts, badland slopes, and active drainages.

Mapped unit: Antrim Shale
Age: 385–360 Ma (Late Devonian)
Rock types: black shale
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 Old Mission State Park

Best months: April to November. Typical highs run 80°F in midsummer and 30°F in midwinter, with winter lows near 17°F.

Climate normals: NOAA 1991-2020 monthlies, OLD MISSION 3SSW station (5 mi away).

Land & collecting status

Generally open to casual rockhounding

Most public-tagged spots sit on BLM, U.S. Forest Service, or other federal land where reasonable hand collecting of common rocks and minerals is allowed. Confirm posted rules and active mining claims before you dig.

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

Nearby rockhounding spots

Other rockhounding spots within driving distance of Old Mission State Park.

Old Mission State Park FAQ

Where is Old Mission State Park?+

Old Mission State Park is in Grand Traverse County, Michigan, at 44.98999, -85.48987.

What rocks and minerals can you find at Old Mission State Park?+

Old Mission State Park is on the rockhounding map but no minerals are listed in our reference. Open RockHoundR to see what other rockhounds have logged.

Is collecting allowed at Old Mission State Park?+

Generally open to casual rockhounding. Most public-tagged spots sit on BLM, U.S. Forest Service, or other federal land where reasonable hand collecting of common rocks and minerals is allowed. Confirm posted rules and active mining claims before you dig. Always confirm current rules with the managing agency before a trip.

What tools should I bring to Old Mission State Park?+

A rock hammer, sturdy gloves, safety glasses, and a collecting bag cover the basics here. Add a spray bottle: wet rock shows color and pattern that dry rock hides.

When is the best time to visit Old Mission State Park?+

The most comfortable months at Old Mission State Park are April to November.

How do I get to Old Mission State Park?+

Open the directions link to navigate to 44.98999, -85.48987 in Google Maps. Some spots are remote, so check road conditions before driving out.

More rockhounding in Michigan

See all 107 Michigan spots →

Open Old Mission State Park on the map

Use the RockHoundR app for live land overlays, weather, geology, directions, and saved finds.