Buffalo: Agate & Chalcedony Rockhounding in Johnson County, Wyoming

Updated July 2026

Buffalo is a mapped rockhounding spot in Johnson County, Wyoming. Reported finds include agate, chalcedony, gastrolith, jasper, petrified wood, and more. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Permission required
County: Johnson County
State: Wyoming
Coordinates: 44.45273, -106.55482

Geology at Buffalo

This spot sits on ground mapped as Wasatch Formation that formed roughly 66 to 34 million years ago. Petrified wood typically shows up as durable float on slopes and in washes cut into ground like this.

Mapped unit: Wasatch Formation
Age: 66–34 Ma (Paleocene to Eocene)
Elevation: 4,300 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 Buffalo

Best months: March to November. Typical highs run 87°F in midsummer and 40°F in midwinter, with winter lows near 20°F.

Climate normals: NOAA 1991-2020 monthlies, BUFFALO JOHNSON CO AP station (10 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 Buffalo

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 Buffalo.

Buffalo FAQ

Where is Buffalo?+

Buffalo is in Johnson County, Wyoming, at 44.45273, -106.55482.

What rocks and minerals can you find at Buffalo?+

Buffalo is reported to produce Agate, Chalcedony, Gastrolith, Jasper, Petrified Wood, Quartz.

Is collecting allowed at Buffalo?+

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 Buffalo?+

A rock hammer, sturdy gloves, and a padded bag cover petrified wood hunting. Most pieces are surface float, so walking slopes and washes beats digging.

When is the best time to visit Buffalo?+

The most comfortable months at Buffalo are March to November.

How do I get to Buffalo?+

Open the directions link to navigate to 44.45273, -106.55482 in Google Maps. Some spots are remote, so check road conditions before driving out.

More rockhounding in Wyoming

See all 92 Wyoming spots →

Open Buffalo on the map

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