Valley Quarry: Copper & Epidote Rockhounding in Adams County, Pennsylvania

Plan your visit

Generally open to casual rockhounding

County

Adams County

State

Pennsylvania

Nearest road

Baltimore Pike

Postcode

17325

Coordinates

39.80342, -77.21259

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 Valley Quarry

Comfortable months (45 to 90°F highs)

Best months: March to December. Typical highs run 86°F in midsummer and 40°F in midwinter, with winter lows near 21°F.

Climate normals: NOAA 1991-2020 monthlies, EISENHOWER NHS station (1 mi away).

Geology at Valley Quarry

This spot sits on Gettysburg Formation, mapped as siltstone mudstone and shale that formed roughly 250 to 200 million years ago. Sedimentary rock like this erodes unevenly, so the most productive collecting is typically along fresh cuts, badland slopes, and active drainages.

Mapped unit

Gettysburg Formation

Age

250–200 Ma (Triassic)

Rock types

siltstone mudstone and shale

Elevation

470 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.

• Pennsylvania Geological Survey
• DCNR state park and state forest rules
• Allegheny National Forest
• Community submissions reviewed against published agency rules