RockHoundR
Download on the App StoreGet it on Google Play

Rattlesnake Mountain: Anhydrite Rockhounding in Park County, Wyoming

Updated June 2026

Rattlesnake Mountain is a mapped rockhounding spot in Park County, Wyoming. Reported finds include anhydrite. Below: coordinates, access notes, nearby spots, and trip-planning links.

Map showing Rattlesnake Mountain in Park County, Wyoming

Quick details

Access
Public area
State
Wyoming

Geology at Rattlesnake Mountain

This spot sits on Madison Limestone or Group, mapped as limestone and dolostone that formed roughly 360 to 325 million years ago. Carbonate rock like this dissolves and weathers readily, so fresh road cuts, quarries, and creek exposures are typically the most productive ground.

Mapped unit
Madison Limestone or Group
Age
360–325 Ma (Mississippian)
Rock types
limestone and dolostone
Elevation
6,960 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 Rattlesnake Mountain

Best months: April to October. Typical highs run 76°F in midsummer and 32°F in midwinter, with winter lows near 13°F.

Climate normals: NOAA 1991-2020 monthlies, BUFFALO BILL DAM station (4 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.

State guidance last verified:

Found at Rattlesnake Mountain

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 Rattlesnake Mountain.

Across the state line from Rattlesnake Mountain

Rattlesnake Mountain is close enough to the Wyoming border that the next-closest rockhounding spots are in a neighboring state. Worth knowing if you are already on the road.

Rattlesnake Mountain FAQ

Where is Rattlesnake Mountain?+
Rattlesnake Mountain is in Park County, Wyoming, at 44.52733, -109.24111.
What rocks and minerals can you find at Rattlesnake Mountain?+
Rattlesnake Mountain is reported to produce Anhydrite.
Is collecting allowed at Rattlesnake Mountain?+
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 Rattlesnake Mountain?+
A rock hammer, sturdy gloves, safety glasses, and a collecting bag cover the basics here. Add a spray bottle: wet rock shows color and pattern that dry rock hides.
When is the best time to visit Rattlesnake Mountain?+
The most comfortable months at Rattlesnake Mountain are April to October.
How do I get to Rattlesnake Mountain?+
Open the directions link to navigate to 44.52733, -109.24111 in Google Maps. Some spots are remote, so check road conditions before driving out.

More rockhounding in Wyoming

See all 82 Wyoming spots →

Open Rattlesnake Mountain on the map

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

Download on the App StoreGet it on Google Play