Mystery Fossil

Data: Hi,
My sister found this seashell fossil in Altamont, California, and asked me to try and do some research on it. I know nothing about the subject but agreed because she has not computer. This fossil is 7" wide and 10" long. Any information you could supply would be great! I'm sending pictures I took with my iphone.

Thanks in advance,
Daniel M.

Send Ideas to: Daniel

Identified: Fossil Inoceramus ( )



  • Its an Inoceramus. What species I have no idea. Mesozoic, likely Cretaceous in age. Best, Chuck P.

  • And Chuck should know. Inoceramidae are pretty featureless shells, but they look Cretaceous to me, probably Inoceramus. It doesn't look Jurassic (eg Retroceramus), which tend to be mytiliform ie somewhat to strongly elongate....Andrew G.


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