Fossil Crinoid (Colorado, USA) - Set of 3 (D)

Sea Lily Fossil
Origin: McCoy, Colorado, USA

These are sea lily fossils.
There are three pieces where the center of the cross-section appears as ① round, ② pentagonal, and ③ flower-shaped.

Few of my personal collection have clean cross-sectional shapes.
Since they are like Kintaro candy (a type of Japanese hard candy with a pattern throughout), I have shaved one side of the cross-section on some.
The surface has been wetted for photography to make the shapes clearer in the pictures.

All of these sea lilies were collected from the same area, found on the ground surface.
They appear to be similar stems, but I don't know if the different center shapes are due to different species or different parts of the same species, as I lack the knowledge.

① Round shapes are the most common, making up about 90% of my collection.
② Pentagonal shapes are about 0.5%. One side of the cross-section has been shaved.
③ Flower shapes make up about 10%, but few have clean cross-sections.
One side of the cross-section has been shaved.
This is my favorite shape, resembling a relief carving from an ancient ruin.
I did not distinguish between ①, ②, and ③ when collecting, so my collection ratio is likely close to the actual ratio.

Sea lilies are not plants; they belong to the echinoderms, like sea urchins, starfish, and sea cucumbers.
A clear explanation can be found in Fossil Sea Lilies in the Illustrated Encyclopedia of Natural Objects, so please search for it. Types ① and ② were described, but ③ was not. ③ may be rare.

The fossil layers in McCoy were a tropical sea near the equator 300 million years ago.

Since these are fossils, they are listed as scratched and dirty.

Shipping will be via Yu-Packet Post Mini.