Union: Feldspar & Moonstone Rockhounding in Northeastern Connecticut Planning Region, Connecticut

Updated June 2026

Union is a mapped rockhounding spot in Northeastern Connecticut Planning Region, Connecticut. Reported finds include feldspar, moonstone, cordierite. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Public area
County: Northeastern Connecticut Planning Region
State: Connecticut
Nearest road: Bigelow Hollow Road
Postcode: 06076
Coordinates: 41.99191, -72.13323

Geology at Union

This spot sits on Upper member [of Bigelow Brook Formation], mapped as schist that formed roughly 540 to 445 million years ago. Metamorphic belts like this often host pegmatite dikes, the coarse-crystal bodies that typically carry beryl, tourmaline, and sheet mica.

Mapped unit: Upper member [of Bigelow Brook Formation]
Age: 540–445 Ma (Cambrian to Ordovician)
Rock types: schist
Elevation: 740 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 Union

Best months: March to November. Typical highs run 81°F in midsummer and 35°F in midwinter, with winter lows near 16°F.

Climate normals: NOAA 1991-2020 monthlies, SOUTHBRIDGE 3 SW station (6 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 Union

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 Union.

Across the state line from Union

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

Union FAQ

Where is Union?+

Union is in Northeastern Connecticut Planning Region, Connecticut, at 41.99191, -72.13323. Nearest road: Bigelow Hollow Road.

What rocks and minerals can you find at Union?+

Union is reported to produce Feldspar, Moonstone, Cordierite.

Is collecting allowed at Union?+

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 Union?+

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 Union?+

The most comfortable months at Union are March to November.

How do I get to Union?+

Open the directions link to navigate to 41.99191, -72.13323 in Google Maps. The nearest road is Bigelow Hollow Road.

More rockhounding in Connecticut

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Open Union on the map

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