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Mazon River

Illinois
Directions
Next site in IllinoisCoal City · 3 mi

Can I collect here?

Pro
See who owns this land and whether it is claimedPro shows the owner, the claim on this spot and every claim within a mile.
Read the collecting rules by land type

Based on our latest records, with claims updated from the BLM on Oct 9, 2026. Land and claims can change quickly, so check before you go.

Minerals on record here

1 mineral

Recorded here: fossil.

Nearby sites

All of Illinois
3 miCoal CityConcretions With Fossil6 miFisher SiteFossil6 miMazon RiverFossil

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About Mazon River

Mazon River is a fossil collection site in Illinois, cataloged in the Paleobiology Database. Fossils here come from the Carbondale Formation, dated to the Westphalian D (309.8–307.4 million years ago). The depositional environment is recorded as deltaic indet and the tectonic setting is cratonic basin. Documented finds include Squirmarius testai.

Geologic setting

Formation
Carbondale
Geologic interval
Westphalian D
Age
309.8–307.4 Ma
Depositional environment
deltaic indet.
Tectonic setting
cratonic basin
Recorded occurrences
1
Geology notes

Illinois basin

Locality notes

No more specific information given

Fossils found here

Squirmarius testai
Cyclostomi · NO_FAMILY_SPECIFIED

Records and references

Data: Paleobiology Database collection 233234 (CC BY 4.0) — view the source record

Getting there

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Questions about Mazon River

Can you collect at Mazon River?

It depends on who owns the land and whether a mining claim covers it. BLM land usually allows hand collecting for personal use, national parks allow none, and private land needs the owner’s permission. Pro members see the owner and any claims at this spot.

What minerals are found at Mazon River?

Fossil.

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Source: Paleobiology Database.