This is a fabulous Utah trilobite of the rare species Amecephalus idahoense.
The trilobite offers a very nice and detailed preservation. The trilobite is also very 3dimensonal preserved. Also the for Amecephalus idahoense  typical ornamentation of the shell is well visibile. The left librigena is partly cast by the glue line from the external mould. All in one it is a wonderful Utah trilobite that you won’t see every day.

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