Calcite or Quartz Brachiopod

Here is a Devonian brachiopod with its internal structure crystallized. The lophophore columns or feeding tubes have turned to calcite or quartz.

I am guessing it was genus Spirifera.

Star of David or Hexagonalis Crinoid

I like to call this the star of David crinoid piece even though it has 7 points. Maybe 4 mm wide from point to point on this piece. Looking on the internet I have not found anything that looks like it but it might not be crinoid stem but maybe a piece of a calyx.

The second picture shows the small rock that the little star fossil is embedded in.

Revised: At a KYANA fossil study session, I was shown a set of articles from the University of Kansas on crinoid stem classification. It had a series of shapes and names for them. One shape was a six pointed star labeled hexagonalis (hex - Greek for six and gonia - Greek for corner or angle). Since this shape has 7 corners, it could be called a heptagonalis (hepta - Greek for seven).

Also since there is a dot in the middle of the shape, you add a prefix to this word above so if the shape in the middle is a circle, cyclohexagonalis or cycloheptagonalis; if ellipse shape in middle then Ellipsahexagonalis or Ellipsoheptagonalis.

Blastoids

Truly, a beautiful fossil and reveals itself out the rock matrix so well. It makes me think of stone flower bud.

These fossils came from Sulphur, Indiana, USA I-64 road exit which is to the west of Louisville, Kentucky. It was collected at the same time as yesterday's Archimedes.

These blastoids are either Pentremites sodoni or Pentremites wellen. They are from the Mississippian period (known outside the United States as Carboniferous) which about 290-350 million years ago. The rock section is Chesterian and the formation these came from was the Haney.