Where to Find Agate in Illinois

Illinois has 5 mapped collecting spots that report agate, spread across 4 counties. The largest share sits in Alexander County with 2 spots. 5 of the spots are on land mapped as publicly accessible.

Standout agate spots in Illinois

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

Fayville
Alexander County
The Mississippi River gravel bars near Fayville and Thebes, at the far southern tip of Illinois, are the state's most productive agate ground, where fortification agate and jasper accumulate in the river sediment.
Hamilton
Hancock County
Hamilton lies on the Mississippi River within the Keokuk geode bed, a Lower Mississippian (Warsaw Formation) zone regarded as one of the finest quartz-geode localities on Earth.
Cordova
Rock Island County
The Mississippi River gravel bars at Cordova are among Illinois's most reliable spots for Lake Superior agate, carried south by glacial meltwater from the agate source region in Minnesota and Wisconsin.

Best counties for agate in Illinois

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

Every agate spot we track in Illinois

Sorted by county. Coordinates open in Google Maps.

Spot	County	Minerals	Coordinates	Access
FayvilleThebes Road	Alexander County	Agate Jasper Diamond	37.1986, -89.4522	Public
ThebesOld Route 3	Alexander County	Agate Jasper	37.2393, -89.4422	Public
HamiltonSouth 9th Street	Hancock County	Agate Jasper Geode	40.3872, -91.3462	Public
Bishop HillCemetary Street	Henry County	Agate Jasper	41.2051, -90.1152	Public
CordovaRiver Road North	Rock Island County	Agate	41.7160, -90.3112	Public

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 Illinois FAQ

Where can you find agate in Illinois?+

The mapped spots concentrate in Alexander County, Hancock County, and Henry County. Every spot on this page appears on the map above with coordinates and access notes.

How many agate spots are mapped in Illinois?+

5 spots across 4 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 Illinois?+

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. 5 of the 5 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 Illinois

Hunt agate in Illinois 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.