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FG-100

Wyoming
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Next site in WyomingFG-98 · 0.5 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.
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Based on our latest records, with claims updated from the BLM on Oct 3, 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 Wyoming
0.5 miFG-98Fossil0.7 miFG-99Fossil0.9 miFG-102Fossil

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About FG-100

FG-100 is a fossil collection site in Wyoming, cataloged in the Paleobiology Database. Fossils here come from the Fort Union Formation, dated to the Cf3 (57.5–56 million years ago). The depositional environment is recorded as fluvial-lacustrine indet and the tectonic setting is intermontane basin. Documented finds include Champsosaurus, Crocodylia, Ectocion osbornianus, Lepisosteus, Plesiadapis dubius.

Geologic setting

Formation
Fort Union
Geologic interval
Cf3
Age
57.5–56 Ma
Depositional environment
fluvial-lacustrine indet.
Tectonic setting
intermontane basin
Recorded occurrences
5
Locality notes

Quad = Jack Horner Res., Township = 54N, Range = 96W, Section = 8

Fossils found here

Champsosaurus
Reptilia · NO_FAMILY_SPECIFIED
Crocodylia
Reptilia
Ectocion osbornianus
Mammalia · Phenacodontidae
Lepisosteus
Osteichthyes · Lepisosteidae
Plesiadapis dubius
Mammalia · Plesiadapidae

Records and references

Data: Paleobiology Database collection 46678 (CC BY 4.0) — view the source record

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Questions about FG-100

Can you collect at FG-100?

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 FG-100?

Fossil.

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Source: Paleobiology Database.