Stanley: Glauberite & Halite Rockhounding in Mountrail County, North Dakota

Updated June 2026

Stanley is a mapped rockhounding spot in Mountrail County, North Dakota. Reported finds include glauberite, halite, thenardite. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Public area
County: Mountrail County
State: North Dakota
Coordinates: 48.40331, -102.48083

Geology at Stanley

This spot sits on Sentinel Butte Formation, mapped as siltstone, claystone, and sandstone that formed roughly 66 to 56 million years ago. Sedimentary rock like this erodes unevenly, so the most productive collecting is typically along fresh cuts, badland slopes, and active drainages.

Mapped unit: Sentinel Butte Formation
Age: 66–56 Ma (Paleocene)
Rock types: siltstone, claystone, and sandstone
Elevation: 2,160 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 Stanley

Best months: April to October. Typical highs run 80°F in midsummer and 18°F in midwinter, with winter lows near 0°F.

Climate normals: NOAA 1991-2020 monthlies, STANLEY 3 NNW station (5 mi away).

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 Stanley

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 Stanley.

Stanley FAQ

Where is Stanley?+

Stanley is in Mountrail County, North Dakota, at 48.40331, -102.48083.

What rocks and minerals can you find at Stanley?+

Stanley is reported to produce Glauberite, Halite, Thenardite.

Is collecting allowed at Stanley?+

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 Stanley?+

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 Stanley?+

The most comfortable months at Stanley are April to October.

How do I get to Stanley?+

Open the directions link to navigate to 48.40331, -102.48083 in Google Maps. Some spots are remote, so check road conditions before driving out.

More rockhounding in North Dakota

See all 20 North Dakota spots →

Open Stanley on the map

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