Fossil in Landscaping Bull Rock (chert)?

[DawnO]

Stumbled upon interesting "imprints" and "casts" in one of our backyard landscaping rocks (Houston).  The landscapers call it "Bull Rock"... I think it is actually "chert".    Looks to be marine invertebrate fossils?  Would that be common or rare in this type of rock?  Wondering if it is worth searching more in the back yard?

 

Edited June 17, 2022 by DawnO
Switched from .heic to .jpg photos

[Plantguy]

Neat finds. I cant speak to Texas gravels, but I've collected in similar gravels in Maryland and the area I was in finding invert bits were very common finds. I spent many an hour as a kid fascinated how many pieces of things you'd find...the tumbling/rounded edges kind of ruined your chances of finding anything complete but I did crack many apart to see more. Occasionally I'd find something more. A pile of rocks always captures my imagination!

 

Regards, Chris