Montrose: Fossil Hunting in Sioux County, Nebraska

Plan your visit

Generally open to casual rockhounding

County

Sioux County

State

Nebraska

Nearest road

Montrose Road

Coordinates

42.92501, -103.73604

Coordinates are approximate. Confirm the exact ground in the RockHoundR app, where land overlays show which agency manages the area.

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.

Access note: Collect on the Oglala National Grassland (USFS) portions only: personal, noncommercial surface collecting up to 25 lb per day, no digging, no fossils or artifacts. The area is a checkerboard of federal grassland and private ranchland; know the boundary and get permission before crossing onto private tracts.

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.

Best time to visit Montrose

Comfortable months (45 to 90°F highs)

Best months: March to November. Typical highs run 90°F in midsummer and 38°F in midwinter, with winter lows near 8°F.

Climate normals: NOAA 1991-2020 monthlies, ARDMORE 1 NW station (8 mi away).

Geology at Montrose

This spot sits on Pierre Shale, mapped as shale that formed roughly 100 to 66 million years ago. Sedimentary layers like these are where fossils are typically preserved, and fresh exposures after rain or in active cuts tend to produce best.

Mapped unit

Pierre Shale

Age

100–66 Ma (Late Cretaceous)

Rock types

shale

Elevation

3,650 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.

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.

• Nebraska National Forests and Grasslands
• Conservation and Survey Division, University of Nebraska
• Nebraska Game and Parks rules
• Community submissions reviewed against published agency rules