Mt. Adams: Agate & Carnelian Rockhounding in Skamania County, Washington

Updated June 2026

Mt. Adams is a mapped rockhounding spot in Skamania County, Washington. Reported finds include agate, carnelian, chalcedony, jasper, quartz. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Permission required
County: Skamania County
State: Washington
Nearest road: Pacific Crest Trail
Coordinates: 46.23593, -121.54738

Geology at Mt. Adams

This spot sits on Mount Adams, volcaniclastic rocks of, debris flows, mapped as volcaniclastic deposits or rocks that formed within roughly the last 12,000 years. Volcanic ground like this is where agate, jasper, and other chalcedony typically form, filling old gas pockets and fracture seams in the flow rock.

Mapped unit: Mount Adams, volcaniclastic rocks of, debris flows
Age: < 1 Ma (Holocene)
Rock types: volcaniclastic deposits or rocks
Elevation: 6,180 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 Mt. Adams

Best months: May to October. Typical highs run 69°F in midsummer and 24°F in midwinter, with winter lows near 11°F.

Climate normals: NOAA 1991-2020 monthlies, MT ADAMS RS station (16 mi away), adjusted for elevation.

Land & collecting status

Permission required before collecting

Requires landowner or agency permission before any collecting. Do not enter without explicit authorization.

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: April 1, 2026

Washington Geological Survey (DNR)
Stonerose Interpretive Center — Visit & rules
BLM Spokane District
Community submissions reviewed against published agency rules

Found at Mt. Adams

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 Mt. Adams.

Across the state line from Mt. Adams

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

Mt. Adams FAQ

Where is Mt. Adams?+

Mt. Adams is in Skamania County, Washington, at 46.23593, -121.54738. Nearest road: Pacific Crest Trail.

What rocks and minerals can you find at Mt. Adams?+

Mt. Adams is reported to produce Agate, Carnelian, Chalcedony, Jasper, Quartz.

Is collecting allowed at Mt. Adams?+

Permission required before collecting. Requires landowner or agency permission before any collecting. Do not enter without explicit authorization. Always confirm current rules with the managing agency before a trip.

What tools should I bring to Mt. Adams?+

Most agate and jasper is surface float: bring a spray bottle, a pick or small shovel, and a sturdy bag. Wet stones show their banding and translucence.

When is the best time to visit Mt. Adams?+

The most comfortable months at Mt. Adams are May to October.

How do I get to Mt. Adams?+

Open the directions link to navigate to 46.23593, -121.54738 in Google Maps. The nearest road is Pacific Crest Trail.

More rockhounding in Washington

See all 92 Washington spots →

Open Mt. Adams on the map

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