Best spot

Cheyenne River: Fairburn Agate Rockhounding in Custer County, South Dakota

Updated June 2026

This locality along the Cheyenne River drainage sits within the core Fairburn agate belt just south of the main Fairburn beds, and the river gravels and surrounding badlands carry the same prized state-gem fortification agate. It offers another productive Fairburn-agate option in the Buffalo Gap grassland country. Reported finds include fairburn agate. Below: coordinates, access notes, nearby spots, and trip-planning links.

Cheyenne River photos

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

1 photo

A Fairburn agate with vivid red and yellow fortification banding around a white quartz center, the state-gem agate of the Cheyenne River drainage

Quick details

Access: Public area
County: Custer County
State: South Dakota
Coordinates: 43.60283, -103.02303

Geology at Cheyenne River

This spot sits on ground mapped as Alluvial deposits that formed within roughly the last 3 million years. Gravels like these concentrate whatever survives the river: agate, jasper, and other tough silica typically show up as rounded, waxy stones.

Mapped unit: Alluvial deposits
Age: 3 Ma to present (Pleistocene to Holocene)
Elevation: 2,740 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 Cheyenne River

Best months: March to November. Typical highs run 90°F in midsummer and 39°F in midwinter, with winter lows near 12°F.

Climate normals: NOAA 1991-2020 monthlies, ORAL station (18 mi away), adjusted for elevation.

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 Cheyenne River

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

Fairburn Agate Encyclopedia →

Nearby rockhounding spots

Other rockhounding spots within driving distance of Cheyenne River.

Across the state line from Cheyenne River

Cheyenne River 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.

Cheyenne River FAQ

Where is Cheyenne River?+

Cheyenne River is in Custer County, South Dakota, at 43.60283, -103.02303.

What rocks and minerals can you find at Cheyenne River?+

Cheyenne River is reported to produce Fairburn Agate.

Is collecting allowed at Cheyenne River?+

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 Cheyenne River?+

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 Cheyenne River?+

The most comfortable months at Cheyenne River are March to November.

How do I get to Cheyenne River?+

Open the directions link to navigate to 43.60283, -103.02303 in Google Maps. Some spots are remote, so check road conditions before driving out.

More rockhounding in South Dakota

See all 43 South Dakota spots →

Open Cheyenne River on the map

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