Manhattan — Rockhounding in Gallatin County, Montana

Manhattan is a mapped rockhounding spot in Gallatin County, Montana. Reported finds include onyx. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Public area
County: Gallatin County
State: Montana
Nearest road: Horseshoe Cottonwood Road
Coordinates: 45.90928, -111.40563

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

BLM Montana — Recreational mineral collecting
Montana Bureau of Mines and Geology
Gem Mountain Sapphire Mine (fee-dig operator)
Community submissions reviewed against published agency rules

Found at Manhattan

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

OnyxEncyclopedia →

Nearby rockhounding spots

Other rockhounding spots within driving distance of Manhattan.

Manhattan FAQ

Where is Manhattan?+

Manhattan is in Gallatin County, Montana, at 45.90928, -111.40563. Nearest road: Horseshoe Cottonwood Road.

What rocks and minerals can you find at Manhattan?+

Manhattan is reported to produce Onyx.

Is collecting allowed at Manhattan?+

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.

How do I get to Manhattan?+

Open the directions link to navigate to 45.90928, -111.40563 in Google Maps. The nearest road is Horseshoe Cottonwood Road.

More rockhounding in Montana

See all 87 Montana spots →

Open Manhattan on the map

Use the RockHoundR app for live land overlays, weather, geology, directions, and saved finds.