Best spot

Grundy County — Rockhounding in Grundy County, Missouri

Grundy County rounds out the cluster of glaciated northern Missouri counties that yield ice-transported Lake Superior agates, with mindat documenting Lake Superior agate from the county. Its creeks and the Thompson and Weldon river gravels rework glacial drift, freeing agate, jasper, and petrified wood. The material is the same banded, tumble-rounded agate prized by Midwest collectors. Reported finds include lake superior agate, jasper, fossils, petrified wood. Below: coordinates, access notes, nearby spots, and trip-planning links.

Grundy County photos

Public image records connected to this spot or its reported material.

1 photo

A polished Lake Superior agate with banded fortification structure, the same tumble rounded ice transported agate documented from Grundy County glacial drift and stream gravels.

Quick details

Access: Public area
County: Grundy County
State: Missouri
Coordinates: 40.11964, -93.52957

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.

Sources: RockHoundR public spot dataset, app land overlays, and local agency review before each trip.

Found at Grundy County

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 Grundy County.

Across the state line from Grundy County

Grundy County is close enough to the Missouri border that the next-closest rockhounding spots are in a neighboring state. Worth knowing if you are already on the road.

Grundy County FAQ

Why is Grundy County one of the best rockhounding spots in Missouri?+

Where is Grundy County?+

Grundy County is in Grundy County, Missouri, at 40.11964, -93.52957.

What rocks and minerals can you find at Grundy County?+

Grundy County is reported to produce Lake Superior Agate, Jasper, Fossils, Petrified Wood.

Is collecting allowed at Grundy County?+

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.

How do I get to Grundy County?+

Open the directions link to navigate to 40.11964, -93.52957 in Google Maps. Some spots are remote — check road conditions before driving out.

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