Girty: Hematite & Magnetite Rockhounding in Armstrong County, Pennsylvania

Updated June 2026

Girty is a mapped rockhounding spot in Armstrong County, Pennsylvania. Reported finds include hematite, magnetite, calcite, chert, pyrite. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Public area
County: Armstrong County
State: Pennsylvania
Nearest road: PA 56;PA 156
Coordinates: 40.63535, -79.40725

Geology at Girty

This spot sits on Allegheny Formation, mapped as sandstone that formed roughly 325 to 300 million years ago. Tough silica like agate, jasper, and chert typically weathers out of beds like these and collects as float in drainages and on deflation surfaces.

Mapped unit: Allegheny Formation
Age: 325–300 Ma (Pennsylvanian)
Rock types: sandstone
Elevation: 1,000 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 Girty

Best months: March to November. Typical highs run 84°F in midsummer and 35°F in midwinter, with winter lows near 17°F.

Climate normals: NOAA 1991-2020 monthlies, FORD CITY 4 S DAM station (8 mi away).

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.

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

Found at Girty

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 Girty.

Across the state line from Girty

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

Girty FAQ

Where is Girty?+

Girty is in Armstrong County, Pennsylvania, at 40.63535, -79.40725. Nearest road: PA 56;PA 156.

What rocks and minerals can you find at Girty?+

Girty is reported to produce Hematite, Magnetite, Calcite, Chert, Pyrite.

Is collecting allowed at Girty?+

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 Girty?+

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 Girty?+

The most comfortable months at Girty are March to November.

How do I get to Girty?+

Open the directions link to navigate to 40.63535, -79.40725 in Google Maps. The nearest road is PA 56;PA 156.

More rockhounding in Pennsylvania

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Open Girty on the map

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