What is it ?

[trusty]

I've had this "Rock" for several years & don/t even remember where I found it. I think it was on a Lake Michigan beach.

Will someone tell me what it is ?

Thanks for looking.

[Harry Pristis]

I've had this "Rock" for several years & don/t even remember where I found it. I think it was on a Lake Michigan beach.

Will someone tell me what it is ?

Thanks for looking.

It appears to be a colonial coral. Many chunks like this were carried by glaciers from Canada. It may be Silurian in age. Do an Internet search for PETOSKEY STONE.

[trusty]

Thanks Harry.

I never thought of Petoskey Stone. I've never seen one this big.

Think I should polish it ?