Best spot

Mound City — Rockhounding in Campbell County, South Dakota

The country around Mound City, west toward the Missouri River, is a documented source of petrified and agatized wood, with occasional opal, weathering out of the banks and gravels of the river and its tributaries. It is one of the better petrified-wood opportunities in the north-central part of the state. Reported finds include petrified wood, opal. Below: coordinates, access notes, nearby spots, and trip-planning links.

Mound City photos

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

1 photo

Petrified wood logs weathering out of badlands strata in the northern Great Plains, the kind of fossil wood found in the Missouri River gravels near Mound City

Quick details

Access: Public area
County: Campbell County
State: South Dakota
Coordinates: 45.72064, -100.23723

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 Mound City

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 Mound City.

Across the state line from Mound City

Mound City is close enough to the South Dakota border that the next-closest rockhounding spots are in a neighboring state. Worth knowing if you are already on the road.

Mound City FAQ

Why is Mound City one of the best rockhounding spots in South Dakota?+

Where is Mound City?+

Mound City is in Campbell County, South Dakota, at 45.72064, -100.23723.

What rocks and minerals can you find at Mound City?+

Mound City is reported to produce Petrified Wood, Opal.

Is collecting allowed at Mound City?+

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 Mound City?+

Open the directions link to navigate to 45.72064, -100.23723 in Google Maps. Some spots are remote — check road conditions before driving out.

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