Jaw bone(?) of a ???

[pliebenberg]

New member, first time posting!

 

This object was located a couple of winters ago in the foothills above Los Gatos, CA at about 700' MSL.  A large oak tree had fallen over and in the rocks brought to the surface (from a depth of about 3') by the uprooted stump was what appeared to be some sort of a fossil jaw.  The inner surface has cavities which very much look like the roots of teeth, especially molars.  It reacted very strongly to a drop of dilute HCl acid.  About 45 grams in weight.  Other fossils found in this area are small "clam" shells, foraminifera, mineralized whale(?) bones, and once I found a shark tooth.  Geology maps show this area is Miocene sedimentary but it's quite close to a boundary of Miocene/Oligocene sedimentary.

 

I haven't a clue if this "jaw" is from a mammal, a fish, turtle, (???) or not a jaw at all.  Very stout whatever it's from.

 

Any ideas will be much appreciated.

 

Regards,

Paul

[Fin Lover]

Welcome to the forum!  Sorry, but I don't think this is a jaw.

[pliebenberg]

1 hour ago, Fin Lover said:

Welcome to the forum!  Sorry, but I don't think this is a jaw.

Thanks!  Any suggestions?

[bockryan]

Could be a partially weathered mold/cast of an ammonite, not sure if the geology around there would allow for that depending on how old the rocks are.