Mill Canyon — Rockhounding in Madison County, Montana

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

Quick details

Access: Public area
County: Madison County
State: Montana
Coordinates: 45.69677, -112.12467

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 Mill Canyon

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

Tourmaline Encyclopedia →

Nearby rockhounding spots

Other rockhounding spots within driving distance of Mill Canyon.

Mill Canyon FAQ

Where is Mill Canyon?+

Mill Canyon is in Madison County, Montana, at 45.69677, -112.12467.

What rocks and minerals can you find at Mill Canyon?+

Mill Canyon is reported to produce Tourmaline.

Is collecting allowed at Mill Canyon?+

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 Mill Canyon?+

Open the directions link to navigate to 45.69677, -112.12467 in Google Maps. Some spots are remote — check road conditions before driving out.

More rockhounding in Montana

See all 87 Montana spots →

Open Mill Canyon on the map

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