Calcite crystals??? Fossilized sand dollar???

[drumrun]

Hello, found what appears to be a clam shell in concreation that has a small opening. Through the opening it appears the inside of the shell is full of crystals. Are they calcite and if so how old is something like this? Same question for the sanddollar, how old would something like that be? Pretty cool and pretty excited. Found along the cost if NC.
Thank you so much for time and input.
Randy

 

[drumrun]

 

[Jason in Enid]

I dont think your sand dollar lump is fossilized. Looks like a concretion instead of a fossil.

 

[drumrun]

I dont think your sand dollar lump is fossilized. Looks like a concretion instead of a fossil.

Well thats a bummer, but I appreciate the feedback. Any info on the clam?