N Umpqua River: Agate & Chalcedony Rockhounding in Douglas County, Oregon

Plan your visit

Generally open to casual rockhounding

County

Douglas County

State

Oregon

Nearest road

Smith Springs Lane

Postcode

97447

Coordinates

43.29774, -122.93905

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.

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 N Umpqua River

Comfortable months (45 to 90°F highs)

Conditions here are workable year-round, with typical highs from 47°F in winter to 85°F in summer.

Climate normals: NOAA 1991-2020 monthlies, IDLEYLD PARK 4 NE station (5 mi away), adjusted for elevation.

Geology at N Umpqua River

This spot sits on Little Butte Volcanics, mapped as lapilli tuff, green, light gray, yellow; andesine to labradorite feldspar phenocrysts; alteration: pyroxene to green clay and iron oxides; matrix: shards and fine ash; carbonized, and silicified wood and leaf fragments; alteration: feldspar partially replaced by zeolites; lithology: dacitic that formed roughly 34 to 5 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

Little Butte Volcanics

Age

34–5 Ma (Oligocene to Miocene)

Rock types

lapilli tuff, green, light gray, yellow; andesine to labradorite feldspar phenocrysts; alteration: pyroxene to green clay and iron oxides; matrix: shards and fine ash; carbonized, and silicified wood and leaf fragments; alteration: feldspar partially replaced by zeolites; lithology: dacitic

Elevation

860 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 Oregon/Washington, Rockhounding & mineral material
• Oregon Department of Geology and Mineral Industries (DOGAMI)
• Oregon Parks and Recreation Department, beach collecting rules
• Community submissions reviewed against published agency rules