Pearl Lake: Staurolite Rockhounding in Grafton County, New Hampshire

Quick details

Access

Public area

County

Grafton County

State

New Hampshire

Nearest road

Scotland Road

Postcode

03585

Coordinates

44.19669, -71.86819

Geology at Pearl Lake

This spot sits on Littleton Formation, undivided, mapped as metagraywacke that formed about 410 million years ago. Sedimentary rock like this erodes unevenly, so the most productive collecting is typically along fresh cuts, badland slopes, and active drainages.

Mapped unit

Littleton Formation, undivided

Age

410–410 Ma (Early Devonian)

Rock types

metagraywacke

Elevation

1,010 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 Pearl Lake

Best months: April to October. Typical highs run 78°F in midsummer and 27°F in midwinter, with winter lows near 8°F.

Climate normals: NOAA 1991-2020 monthlies, BENTON 5 SW station (12 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.

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

Found at Pearl Lake

Each chip opens all spots that produce that material; the encyclopedia link opens the full ID and field guide.

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