Catoctin Mountain: Copper Rockhounding in Frederick County, Maryland

Quick details

Access

Permission required

County

Frederick County

State

Maryland

Nearest road

Manahan Road

Postcode

21780

Coordinates

39.65523, -77.47098

Geology at Catoctin Mountain

This spot sits on Metarhyolite and Aasociated Pyroclastic Sediments, mapped as metarhyolite that formed roughly 2500 to 540 million years ago. Copper minerals such as malachite and chrysocolla typically show up where mineralized rock like this has weathered and oxidized near old workings.

Mapped unit

Metarhyolite and Aasociated Pyroclastic Sediments

Age

2500–540 Ma (Proterozoic)

Rock types

metarhyolite

Elevation

1,650 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 Catoctin Mountain

Best months: March to November. Typical highs run 83°F in midsummer and 39°F in midwinter, with winter lows near 23°F.

Climate normals: NOAA 1991-2020 monthlies, CATOCTIN MTN PARK station (1 mi away).

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.

Sources: RockHoundR public spot dataset, app land overlays, and local agency review before each trip.

Found at Catoctin Mountain

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

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