Ruby Dam: Garnet Rockhounding in Madison County, Montana

Updated August 2026

Ruby Dam is a mapped rockhounding spot in Madison County, Montana. Reported finds include garnet. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Public area
County: Madison County
State: Montana
Nearest road: Upper Ruby Road
Postcode: 59710
Coordinates: 45.23832, -112.10758

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 Ruby Dam

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

Garnet Encyclopedia →

Nearby rockhounding spots

Other rockhounding spots within driving distance of Ruby Dam.

Across the state line from Ruby Dam

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

Ruby Dam FAQ

Where is Ruby Dam?+

Ruby Dam is in Madison County, Montana, at 45.23832, -112.10758. Nearest road: Upper Ruby Road.

What rocks and minerals can you find at Ruby Dam?+

Ruby Dam is reported to produce Garnet.

Is collecting allowed at Ruby Dam?+

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 Ruby Dam?+

A rock hammer, a sieve, and a small shovel work well for garnet-type minerals, which concentrate as resistant grains in soils and creek gravels.

How do I get to Ruby Dam?+

Open the directions link to navigate to 45.23832, -112.10758 in Google Maps. The nearest road is Upper Ruby Road.

More rockhounding in Montana

See all 106 Montana spots →

Open Ruby Dam on the map

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