What is this?

[TxMark]

I am a contractor and found this in 2004 in Austin, TX on an empty house lot. Probably boring to yall but was just curious as to what it was.

I'm thinking a snail but would like to know the real name of it as I have no knowledge about this kind of thing. Currently being used as a paper weight. 

The dimensions are  168mm wide 127mm deep 99mm tall. 2.63 kg

 

Thank you for your help!

 

Mark

[grandpa]

Exogyra ponderosa, a large fossil oyster from the Upper Cretaceous. 

[Creek - Don]

They are found all over North, East, Central Texas. Average size is about 3 inches, but occasionally find ones that are 6 inches. 

[TxMark]

Thank you so much! I really appreciate it.

I have found a wealth of info now with the correct name. 

 

Thanks