"What Is It???" Wednesday: No Chunk of Chalk

A few weeks ago I traveled 100 miles round trip to take a look at Dot Moore's collection of the following.  Particularly specimen A....WHAT IS IT???  What does it tell us about Florida's past?

Correct answer gets a DVD on the topic!  I'd tell you what it is, but then you'd know what IT is.

WHAT IS IT???

Specimen A

Text and images: Sarah Miller, FPAN staff