Poison Strip: Carnotite & Agate Rockhounding in Grand County, Utah

Plan your visit

Confirm rules before collecting

County

Grand County

State

Utah

Nearest road

Yellow Cat Road

Coordinates

38.84790, -109.52869

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

Land & collecting status

Confirm rules before collecting

Land status here is not confirmed. Verify with the managing agency before collecting, federal, state, and tribal rules differ.

Access note: BLM records active mining claims in this area. Collecting from inside an active claim needs the claim holder's permission.

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 Poison Strip

Comfortable months (45 to 90°F highs)

Best months: February to May. Typical highs run 99°F in midsummer and 40°F in midwinter, with winter lows near 14°F. Summer heat here is intense, so carry more water than you think you need and work the early morning.

Climate normals: NOAA 1991-2020 monthlies, DEWEY station (13 mi away), adjusted for elevation.

Geology at Poison Strip

This spot sits on ground mapped as Salt Wash Member of Morrison Formation that formed roughly 160 to 145 million years ago. Petrified wood typically comes from volcanic ash beds like the ones associated with this ground, where buried forests were slowly replaced by silica.

Mapped unit

Salt Wash Member of Morrison Formation

Age

160–145 Ma (Late Jurassic)

Elevation

4,670 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.

State guidance last verified: April 1, 2026

• BLM Utah, Rockhounding overview
• Utah Geological Survey, collecting guidelines
• SITLA, surface use rules
• Community submissions reviewed against published agency rules