I googled those terms but came up empty, here are three photos with a ruler for scale:
The hole and scratches are my dog's teeth, so as you can tell, it is strong yet not brittle. When you shake it, it rattles, like maybe there are seeds in there.
It's from a public irrigated park in a Northern Hemisphere hot desert climate (BWh) region, and I picked it up today, so spring time if that will help.
My dog is usually the one to find it, and we play fetch with it.