Hi Robert, this is some sort of scallop (Pectenid bivalve). The age of the rocks is difficult to determine if there is no locality data attached to the specimen and the wings (which are helpful in diagnosis) are not complete. Sorry not to be able to be more helpful.
says that "Bivalves have inhabited the Earth for over 500 million years. They first appeared in the Middle Cambrian, about 300 million years before the dinosaurs." Guess because of this it's hard to tell the exact period, but I know that at some point the Carpathians were a sea bed. This was found in Piatra Neamt region. oh, and there were plenty like this one. got this from my uncle, was a gift, he knew about my passion about fossils.
Any guess about the other one, Fiona?
Is it an egg?
I for one I think it is. Think might be a new species?
the same as the one above, I have no clue about how old this might be.