Fort Washakie: Moss Agate & Chalcedony Rockhounding in Fremont County, Wyoming

Updated July 2026

Fort Washakie is a mapped rockhounding spot in Fremont County, Wyoming. Reported finds include moss agate, chalcedony, jasper. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Permission required
County: Fremont County
State: Wyoming
Coordinates: 43.13182, -108.97879

Geology at Fort Washakie

This spot sits on Alluvium and Colluvium, mapped as clay, silt, and sand 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 and Colluvium
Age: 3 Ma to present (Pleistocene to Holocene)
Rock types: clay, silt, and sand
Elevation: 5,860 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 Fort Washakie

Best months: March to October. Typical highs run 84°F in midsummer and 35°F in midwinter, with winter lows near 7°F.

Climate normals: NOAA 1991-2020 monthlies, DIVERSION DAM station (7 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.

State guidance last verified: April 1, 2026

BLM Wyoming
Wyoming State Geological Survey
Fossil Butte National Monument
Community submissions reviewed against published agency rules

Found at Fort Washakie

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 Fort Washakie.

Fort Washakie FAQ

Where is Fort Washakie?+

Fort Washakie is in Fremont County, Wyoming, at 43.13182, -108.97879.

What rocks and minerals can you find at Fort Washakie?+

Fort Washakie is reported to produce Moss Agate, Chalcedony, Jasper.

Is collecting allowed at Fort Washakie?+

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 Fort Washakie?+

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 Fort Washakie?+

The most comfortable months at Fort Washakie are March to October.

How do I get to Fort Washakie?+

Open the directions link to navigate to 43.13182, -108.97879 in Google Maps. Some spots are remote, so check road conditions before driving out.

More rockhounding in Wyoming

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Open Fort Washakie on the map

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