need help identifying a shark egg please

[sand tiger]

I purchased this egg and was told it was a guitarfish, one problem .... guitarfish dont lay eggs, if there is someone that could please help me I would greatly appreciate it. It is as big as my hand and you really cannot see through the case whatsoever.
Thank you in advance

 

[tannersmith200]

hey
how much was it?
if it was 30-50 bucks it may have been a cat shark. not sure though. is the egg clear enough to see inside it? do you see shark squirming around in there? if its black and white banded then its prob a cat shark.
just a guess