Where: Illinois · North America · approx. 40.41, -91.34 (vicinity only)
Why this spot: Mississippian Warsaw Formation geodes
What turns up: Keokuk geodes lined with quartz, calcite and pyrite
Access: Permission required.
Weather out of creek banks in Hancock County; most sites are private, ask permission.
Open in Mudlark Map →
Satellite view, historic-map overlays, tide/flow context and field notes are in the app. Exact research detail is part of Pro.
Pins are approximate by design. This page is historical research, not permission to dig. Check ownership and local law first.