Coprolite with crystals?

[ScienceGirl]

Hi! My name is Annika and I'm younger than you think. Anyway, I sliced open a dinosaur coprolite the other day and I was surprised to find crystals! The camera won't capture it but there's the poop!

[Thomas.Dodson]

Hi Annika.

 

Because coprolites, like other fossils, have had most of their composition replaced by mineral structure you often find very nice crystals in fossils. Sometimes a broken or cut specimen displays crystals that make an ordinary fossil into a more showy piece. Here are some simple examples of variety I quickly photographed.  A Mactra warrenana bivalve,  a Juresania nebrascana brachiopod, a pyritized cephalopod, and some poorly preserved wood mostly replaced by opal.