Thunder Creek District: Silver Rockhounding in Skagit County, Washington

Updated June 2026

Thunder Creek District is a mapped rockhounding spot in Skagit County, Washington. Reported finds include silver. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Permission required
County: Skagit County
State: Washington
Nearest road: Thunder Creek Trail
Coordinates: 48.52126, -121.01484

Geology at Thunder Creek District

This spot sits on Cascade Pass, tonalite of, mapped as tonalite that formed roughly 23 to 5 million years ago. Plutonic rock like this weathers slowly into grus and boulders, and the most productive collecting is typically in weathered zones and drainages.

Mapped unit: Cascade Pass, tonalite of
Age: 23–5 Ma (Miocene)
Rock types: tonalite
Elevation: 4,600 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 Thunder Creek District

Best months: May to September. Typical highs run 67°F in midsummer and 25°F in midwinter, with winter lows near 18°F.

Climate normals: NOAA 1991-2020 monthlies, ROSS DAM station (14 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 Thunder Creek District

Each chip opens all spots that produce that material; the encyclopedia link opens the full ID and field guide.

Silver Encyclopedia →

Nearby rockhounding spots

Other rockhounding spots within driving distance of Thunder Creek District.

Thunder Creek District FAQ

Where is Thunder Creek District?+

Thunder Creek District is in Skagit County, Washington, at 48.52126, -121.01484. Nearest road: Thunder Creek Trail.

What rocks and minerals can you find at Thunder Creek District?+

Thunder Creek District is reported to produce Silver.

Is collecting allowed at Thunder Creek District?+

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 Thunder Creek District?+

A rock hammer, gloves, and safety glasses cover old mining-district ground. Stay out of shafts and adits; the best specimens typically come from dump piles.

When is the best time to visit Thunder Creek District?+

The most comfortable months at Thunder Creek District are May to September.

How do I get to Thunder Creek District?+

Open the directions link to navigate to 48.52126, -121.01484 in Google Maps. The nearest road is Thunder Creek Trail.

More rockhounding in Washington

See all 92 Washington spots →

Open Thunder Creek District on the map

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