A Dendrites Forest

My cousin gave me some pictures of these dendrites. It reminds me of looking down on little trees. He did not tell me if he or his brother found them but it is a nice find.

These manganese oxide deposits for the most part have a well defined form.

Productella spinulicosta - Devonian Spiny Brachiopod

UPDATE: I originally labeled this as a spiny snail but after more research it is a spiny brachiopod.  The descriptions have been now fixed.

Here is a Devonian brachiopod a friend found on his visit to Louisville. It has 5 spines visible and is around 2 cm in diameter. It is sharing rock with several brachiopods and a horn coral.

It appears to be a Productella spinulicosta (Hall, 1867) in the Jeffersonville Limestone.  Might also be known as Spinulicosta spinulicosta (how original).

According to this Kentucky Geological Survey page, the Jeffersonville Limestone is similar to the Onondaga Limestone of New York and the Grand Tower of Illinois (Savage, 1931).

Fossil Hunting on Memorial Day Weekend

I had a fun and educational experience on Sunday visiting with a fellow fossil enthusiast at a local Devonian roadcut. Here is a nice find of a spiny brachiopod. It looks to be a Productella spinulicosta (Hall) in the Jeffersonville Limestone. The partial brachiopod to its left in the picture is some sort of spirifer.

Large coral head embedded in the rock wall.

Large horn coral embedded into the wall.

Maybe a distant relative to the trilobite?

Calcite crystals where once a brachiopod existed?