Where to Find Jasper in Montana
Montana has 18 mapped collecting spots that report jasper, spread across 10 counties. The largest share sits in Yellowstone County with 4 spots. 15 of the spots are on land mapped as publicly accessible.
Spot list checked against source data on April 1, 2026.
Every jasper spot we track in Montana
Best spotPryor MountainsBig Horn County, MontanaPermission required · Fossil, Agate, Chalcedony +2
Best spotYellowstone River (Billings area)Yellowstone County, MontanaPublic access · Montana Agate, Chalcedony, Chert +1- Best spotGlendiveDawson County, MontanaPublic access · Agate, Jasper, Moss Opal
Big Horn CanyonBig Horn County, MontanaPermission required · Agate, Chalcedony, Jasper +2
CarbellaPark County, MontanaPublic access · Agate, Jasper, Petrified Wood +1- Jefferson RiverMadison County, MontanaPublic access · Agate, Chalcedony, Jasper +1
- MinerPark County, MontanaPublic access · Agate, Chalcedony, Jasper +1
- Yellowstone River - Black Bridge Boat LaunchDawson County, MontanaPublic access · Montana Moss Agate, Petrified Wood, Jasper +1
- Yellowstone River - Blue Creek AccessYellowstone County, MontanaPublic access · Montana Moss Agate, Petrified Wood, Jasper +1
- Yellowstone River - Bratten Fishing AccessSweet Grass County, MontanaPublic access · Montana Moss Agate, Petrified Wood, Jasper +1
- Yellowstone River - Bundy Bridge Fishing AccessYellowstone County, MontanaPublic access · Montana Moss Agate, Petrified Wood, Jasper +1
- Yellowstone River - Holmgren Fishing AccessStillwater County, MontanaPublic access · Montana Moss Agate, Petrified Wood, Jasper +1
- Yellowstone River - Laurel Sportsman AccessYellowstone County, MontanaPublic access · Montana Moss Agate, Petrified Wood, Jasper +1
- Yellowstone River - Myers Bridge AccessTreasure County, MontanaPublic access · Montana Moss Agate, Petrified Wood, Jasper +1
- Yellowstone River - Pelican Fishing AccessSweet Grass County, MontanaPublic access · Montana Moss Agate, Petrified Wood, Jasper +1
- Yellowstone River - Rosebud AccessRosebud County, MontanaPublic access · Montana Moss Agate, Petrified Wood, Jasper +1
- TerryPrairie County, MontanaPublic access · Petrified Wood, Chalcedony, Jasper
- Finnegan RidgeMadison County, MontanaPermission required · Chert, Jasper
Standout jasper spots in Montana
Hand-picked from the full list above, with the reason each one earns a trip.
Pryor Mountains
Big Horn County
The Pryor Mountains stand out for Dryhead-style agate, with Mindat listing agate and chalcedony from the range and a named Dryhead Agate Mine in the Bighorn River area.
Glendive
Dawson County
Glendive sits in eastern Montana's Yellowstone River agate belt, where gravel bars and nearby breaks are known for agate, jasper, and petrified-wood style silica material.
Yellowstone River (Billings area)
Yellowstone County
The Billings reach of the Yellowstone River is a benchmark Montana agate setting, where river gravels carry chalcedony, jasper, chert, and dendritic moss agate.
Best counties for jasper in Montana
Ranked by the number of mapped jasper spots. County links open the full rockhounding page for that county.
- Yellowstone County4 spots
- Big Horn County2 spots
- Dawson County2 spots
- Madison County2 spots
- Park County2 spots
- Sweet Grass County2 spots
- Prairie County1 spot
- Rosebud County1 spot
- Stillwater County1 spot
- Treasure County1 spot
Before you go
Read the jasper identification guide so you know what a keeper looks like in the field: Jasper in the encyclopedia.
Jasper in Montana FAQ
Where can you find jasper in Montana?+
How many jasper spots are mapped in Montana?+
Is it legal to collect jasper in Montana?+
Where else to find jasper
More minerals to hunt in Montana
Hunt jasper 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.
