Cuprum: Garnet & Epidote Rockhounding in Adams County, Idaho

Updated June 2026

Cuprum is a mapped rockhounding spot in Adams County, Idaho. Reported finds include garnet, epidote. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Public area
County: Adams County
State: Idaho
Nearest road: Forest Road 106
Coordinates: 45.10301, -116.67296

Geology at Cuprum

This spot sits on Blue Mountains island arc, Wallowa terrane, Seven Devils Group, undivided, mapped as greenstone basalt, andesite, and keratophyre that formed roughly 300 to 200 million years ago. Volcanic ground like this weathers into rocky slopes and float, and fresh exposures in cuts and drainages are usually the most productive places to look.

Mapped unit: Blue Mountains island arc, Wallowa terrane, Seven Devils Group, undivided
Age: 300–200 Ma (Permian to Triassic)
Rock types: greenstone basalt, andesite, and keratophyre
Elevation: 5,070 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 Cuprum

Best months: April to October. Typical highs run 81°F in midsummer and 26°F in midwinter, with winter lows near 5°F.

Climate normals: NOAA 1991-2020 monthlies, NEW MEADOWS RS station (21 mi away), adjusted for elevation.

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.

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

Idaho Panhandle National Forests — Emerald Creek
Idaho Geological Survey
Spencer Opal Mines (fee-dig operator)
Community submissions reviewed against published agency rules

Found at Cuprum

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 Cuprum.

Across the state line from Cuprum

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

Cuprum FAQ

Where is Cuprum?+

Cuprum is in Adams County, Idaho, at 45.10301, -116.67296. Nearest road: Forest Road 106.

What rocks and minerals can you find at Cuprum?+

Cuprum is reported to produce Garnet, Epidote.

Is collecting allowed at Cuprum?+

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. Always confirm current rules with the managing agency before a trip.

What tools should I bring to Cuprum?+

A rock hammer, a sieve, and a small shovel work well for garnet-type minerals, which concentrate as resistant grains in soils and creek gravels.

When is the best time to visit Cuprum?+

The most comfortable months at Cuprum are April to October.

How do I get to Cuprum?+

Open the directions link to navigate to 45.10301, -116.67296 in Google Maps. The nearest road is Forest Road 106.

More rockhounding in Idaho

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Open Cuprum on the map

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