Here is a very small (5 mm in diameter) crinoid calyx from Crawford County, Indiana. Using University of Kentucky Dr. Chesnut's
webpage I believe it is called
Cymbiocrinus (Kirk, 1944) and is from the Mississippian period.
It has a nice brownish-tan tint which gives it move visual depth. This is the bottom of the calyx where it attached to the stem and on the other side only small fragments of its arms remain. It is still embedded in a rock fragment with a lot stem pieces.