UPDATE (11/19/2017): The long semi-transparent specimens in the images might be a sponge spicule. I was reading the a book entitled  On ...

This appears to be a Paraconularia magna fossil. It was found in the Cisco group Finis Shale of Jack County Texas. It is from the Pennsy...

The fossil shown here is an Mariacrinus carleyi crinoid calyx found in the Waldron Shale of Davidson County, Tennessee, USA. It was found...