Red Shirt: Agate & Chalcedony Rockhounding in Oglala Lakota County, South Dakota

Updated July 2026

Red Shirt is a mapped rockhounding spot in Oglala Lakota County, South Dakota. Reported finds include agate, chalcedony, jasper. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Permission required
County: Oglala Lakota County
State: South Dakota
Nearest road: Tatanka Numpa Road
Coordinates: 43.67413, -102.89909

Geology at Red Shirt

This spot sits on Alluvium, mapped as coarse alluvium and fine alluvium 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: Alluvium
Age: 3 Ma to present (Quaternary)
Rock types: coarse alluvium and fine alluvium
Elevation: 2,660 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 Red Shirt

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 (26 mi away), adjusted for elevation.

Land & collecting status

Permission required before collecting

Requires landowner or agency permission before any collecting. Do not enter without explicit authorization.

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 Red Shirt

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 Red Shirt.

Across the state line from Red Shirt

Red Shirt 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.

Red Shirt FAQ

Where is Red Shirt?+

Red Shirt is in Oglala Lakota County, South Dakota, at 43.67413, -102.89909. Nearest road: Tatanka Numpa Road.

What rocks and minerals can you find at Red Shirt?+

Red Shirt is reported to produce Agate, Chalcedony, Jasper.

Is collecting allowed at Red Shirt?+

Permission required before collecting. Requires landowner or agency permission before any collecting. Do not enter without explicit authorization. Always confirm current rules with the managing agency before a trip.

What tools should I bring to Red Shirt?+

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 Red Shirt?+

The most comfortable months at Red Shirt are March to November.

How do I get to Red Shirt?+

Open the directions link to navigate to 43.67413, -102.89909 in Google Maps. The nearest road is Tatanka Numpa Road.

More rockhounding in South Dakota

See all 43 South Dakota spots →

Open Red Shirt on the map

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