I don’t know what is made of. It is in a rock.
It’s about the size of the palm of your hand
Crinoid Fossil Plate
Excavation Source: Not given
Measurements: Not given
Crinoids (commonly called sea lilies) are marine animals, not plants. As echinoderms, they are closely related to starfish, sea urchins, and brittle stars.
They first appeared 488 million years ago during the Ordovician period.
This specimen appears to be from a limestone seabed section.