Fossil echinoids?

[Desrosiers1718]

I’ve found two of these in a gravel area in my front apartment area I remember buying the bags at a popular hardware store,  I was told they are Echinoids,  at first I thought they must have been something I collected and threw there but these are not common in my part of California.   As far as I know.  Any idea what species these are and where they might have originated?   I’m tempted to buy another bag.   

[Coco]

There are too few left to determine anything other than irregular sea urchin.

 

Maybe the age of the field might help a little. Miocene ?

 

Coco

Edited May 22, 2023 by Coco

[rocket]

looks a bit like a spatangoid sea urchin, but without age or locality it would be hard to determine it

 

[caterpillar]

8 hours ago, Desrosiers1718 said:

I’m tempted to buy another bag.   

 

You must first ask the seller if he knows where the gravel comes from

[Desrosiers1718]

Ok thanks everyone.