Gaithersburg: Serpentine & Steatite Rockhounding in Montgomery County, Maryland

Updated June 2026

Gaithersburg is a mapped rockhounding spot in Montgomery County, Maryland. Reported finds include serpentine, steatite. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Public area
County: Montgomery County
State: Maryland
Nearest road: Lower Magruder Trail
Postcode: 20882
Coordinates: 39.22853, -77.19030

Geology at Gaithersburg

This spot sits on quaternary alluvium, mapped as gravel that formed within roughly the last 12,000 years. Loose deposits like these are float-collecting ground: erosion keeps moving durable rocks and minerals into gravel bars, cutbanks, and washes.

Mapped unit: quaternary alluvium
Age: < 1 Ma (Holocene)
Rock types: gravel
Elevation: 430 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 Gaithersburg

Best months: March to November. Typical highs run 85°F in midsummer and 40°F in midwinter, with winter lows near 25°F.

Climate normals: NOAA 1991-2020 monthlies, DAMASCUS 3 SSW station (3 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 Gaithersburg

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 Gaithersburg.

Across the state line from Gaithersburg

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

Gaithersburg FAQ

Where is Gaithersburg?+

Gaithersburg is in Montgomery County, Maryland, at 39.22853, -77.19030. Nearest road: Lower Magruder Trail.

What rocks and minerals can you find at Gaithersburg?+

Gaithersburg is reported to produce Serpentine, Steatite.

Is collecting allowed at Gaithersburg?+

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 Gaithersburg?+

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 Gaithersburg?+

The most comfortable months at Gaithersburg are March to November.

How do I get to Gaithersburg?+

Open the directions link to navigate to 39.22853, -77.19030 in Google Maps. The nearest road is Lower Magruder Trail.

More rockhounding in Maryland

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Open Gaithersburg on the map

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