Gay Head: Alum & Amber Rockhounding in Dukes County, Massachusetts

Updated July 2026

Gay Head is a mapped rockhounding spot in Dukes County, Massachusetts. Reported finds include alum, amber. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Permission required
County: Dukes County
State: Massachusetts
Nearest road: Field Loop
Postcode: 02525
Coordinates: 41.34528, -70.83685

Geology at Gay Head

This spot sits on sediments, mapped as fine alluvium and coarse alluvium that formed roughly 145 to 66 million years ago. Loose deposits like these are float-collecting ground: erosion keeps moving durable rocks and minerals into gravel bars, cutbanks, and washes.

Mapped unit: sediments
Age: 145–66 Ma (Cretaceous)
Rock types: fine alluvium and coarse alluvium
Elevation: 90 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 Gay Head

Best months: March to December. Typical highs run 79°F in midsummer and 39°F in midwinter, with winter lows near 23°F.

Climate normals: NOAA 1991-2020 monthlies, VINEYARD HAVEN MARTHAS VINEYAR station (12 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 Gay Head

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 Gay Head.

Across the state line from Gay Head

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

Gay Head FAQ

Where is Gay Head?+

Gay Head is in Dukes County, Massachusetts, at 41.34528, -70.83685. Nearest road: Field Loop.

What rocks and minerals can you find at Gay Head?+

Gay Head is reported to produce Alum, Amber.

Is collecting allowed at Gay Head?+

Permission required before collecting. Requires landowner or agency permission before any collecting. Do not enter without explicit authorization. Always confirm current rules with the managing agency before a trip.

What tools should I bring to Gay Head?+

A rock hammer, sturdy gloves, safety glasses, and a collecting bag cover the basics here. Add a spray bottle: wet rock shows color and pattern that dry rock hides.

When is the best time to visit Gay Head?+

The most comfortable months at Gay Head are March to December.

How do I get to Gay Head?+

Open the directions link to navigate to 41.34528, -70.83685 in Google Maps. The nearest road is Field Loop.

More rockhounding in Massachusetts

See all 45 Massachusetts spots →

Open Gay Head on the map

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