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Where to Find Agate in Montana

Montana has 10 mapped collecting spots that report agate, spread across 6 counties. The largest share sits in Park County with 3 spots. 7 of the spots are on land mapped as publicly accessible.

Spot list checked against source data on April 1, 2026.

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Every agate spot we track in Montana

Standout agate spots in Montana

Hand-picked from the full list above, with the reason each one earns a trip.

Best counties for agate in Montana

Ranked by the number of mapped agate spots. County links open the full rockhounding page for that county.

Before you go

Read the agate identification guide so you know what a keeper looks like in the field: Agate in the encyclopedia.

Agate in Montana FAQ

Where can you find agate in Montana?+
The mapped spots concentrate in Park County, Big Horn County, and Gallatin County. Every spot on this page is on the map, and each spot's own page has its coordinates and access notes.
How many agate spots are mapped in Montana?+
10 spots across 6 counties. The RockHoundR app keeps the same spots on an offline map with public land overlays, geology layers, and your saved finds.
Is it legal to collect agate in Montana?+
Hand collecting of common rocks and minerals in small amounts for personal use is generally allowed on BLM and U.S. Forest Service land, with limits set by the local field office. National parks, most state parks, and tribal land are closed to collecting. 7 of the 10 mapped spots here sit on land marked public. Always confirm current rules with the managing agency before you dig.

Where else to find agate

More minerals to hunt in Montana

Hunt agate in Montana with the map in your pocket

RockHoundR puts these spots on an offline map with BLM and Forest Service overlays, geology layers, and a log for your finds.

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