Porcupine Hill Quarry: Albite & Almandine Garnet Rockhounding in Sagadahoc County, Maine

Updated June 2026

Porcupine Hill Quarry is a mapped rockhounding spot in Sagadahoc County, Maine. Reported finds include albite, almandine garnet, beryl, biotite, columbite, and more. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Public area
County: Sagadahoc County
State: Maine
Nearest road: Turkey Run
Postcode: 04086
Coordinates: 43.95947, -69.98384

Geology at Porcupine Hill Quarry

This spot sits on Z Cushing Formation, mapped as felsic volcanic and mafic volcanic that formed roughly 1000 to 445 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: Z Cushing Formation
Age: 1000–445 Ma (Neoproterozoic to Ordovician)
Rock types: felsic volcanic and mafic volcanic
Elevation: 180 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 Porcupine Hill Quarry

Best months: April to November. Typical highs run 79°F in midsummer and 30°F in midwinter, with winter lows near 12°F.

Climate normals: NOAA 1991-2020 monthlies, BRUNSWICK NAS station (5 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.

State guidance last verified: April 1, 2026

Maine Geological Survey
Maine Mineral & Gem Museum
Acadia National Park rules
Community submissions reviewed against published agency rules

Found at Porcupine Hill Quarry

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 Porcupine Hill Quarry.

Across the state line from Porcupine Hill Quarry

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

Porcupine Hill Quarry FAQ

Where is Porcupine Hill Quarry?+

Porcupine Hill Quarry is in Sagadahoc County, Maine, at 43.95947, -69.98384. Nearest road: Turkey Run.

What rocks and minerals can you find at Porcupine Hill Quarry?+

Porcupine Hill Quarry is reported to produce Albite, Almandine Garnet, Beryl, Biotite, Columbite, Green Elbaite Tourmaline, Fluorapatite, Quartz, Schorl.

Is collecting allowed at Porcupine Hill Quarry?+

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 Porcupine Hill Quarry?+

A rock hammer, a pry bar, gloves, and safety glasses suit pegmatite ground. Work weathered zones and check dump piles; coarse crystals often sit in decomposed rock.

When is the best time to visit Porcupine Hill Quarry?+

The most comfortable months at Porcupine Hill Quarry are April to November.

How do I get to Porcupine Hill Quarry?+

Open the directions link to navigate to 43.95947, -69.98384 in Google Maps. The nearest road is Turkey Run.

More rockhounding in Maine

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Open Porcupine Hill Quarry on the map

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