Acton Lead Mines: Andalusite & Arsenopyrite Rockhounding in York County, Maine

Updated June 2026

Acton Lead Mines is a mapped rockhounding spot in York County, Maine. Reported finds include andalusite, arsenopyrite, bornite, chalcopyrite, galena, and more. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Public area
County: York County
State: Maine
Nearest road: Orchard Road
Postcode: 04001
Coordinates: 43.48316, -70.91040

Geology at Acton Lead Mines

This spot sits on Rindgemere Formation lower member, mapped as mudstone and limestone that formed roughly 445 to 360 million years ago. Carbonate rock like this dissolves and weathers readily, so fresh road cuts, quarries, and creek exposures are typically the most productive ground.

Mapped unit: Rindgemere Formation lower member
Age: 445–360 Ma (Silurian to Devonian)
Rock types: mudstone and limestone
Elevation: 720 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 Acton Lead Mines

Best months: April to November. Typical highs run 80°F in midsummer and 30°F in midwinter, with winter lows near 8°F.

Climate normals: NOAA 1991-2020 monthlies, SANFORD 2 NNW station (7 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

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

Found at Acton Lead Mines

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 Acton Lead Mines.

Across the state line from Acton Lead Mines

Acton Lead Mines 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.

Acton Lead Mines FAQ

Where is Acton Lead Mines?+

Acton Lead Mines is in York County, Maine, at 43.48316, -70.91040. Nearest road: Orchard Road.

What rocks and minerals can you find at Acton Lead Mines?+

Acton Lead Mines is reported to produce Andalusite, Arsenopyrite, Bornite, Chalcopyrite, Galena, Goethite, Gold, Pyrite, Pyrrhotite, Quartz, Silver, Sphalerite.

Is collecting allowed at Acton Lead Mines?+

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 Acton Lead Mines?+

A rock hammer, gloves, and safety glasses are enough for oxidized copper ground. Look for green and blue staining on weathered rock and in old dump piles.

When is the best time to visit Acton Lead Mines?+

The most comfortable months at Acton Lead Mines are April to November.

How do I get to Acton Lead Mines?+

Open the directions link to navigate to 43.48316, -70.91040 in Google Maps. The nearest road is Orchard Road.

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