Lyriocrinus Crinoid Calyx Cup

This fossil appears to be the bottom of a Lyriocrinus calyx cup found in the Waldron Shale of Clark County, Indiana. It is dated to the Middle Silurian Period (425-419 million years ago). Here is a blog post showing an arm fragment of this type of crinoid (blog post here).

Cryptolithus Ordovician Trilobite Fragment

This image shows a Cryptolithus tessellatus fragment found years ago.  It existed in the Ordovician Period. The fossil plate was found in the Kope Formation of Carroll County, Kentucky. When cleaning fossils recently, it was in a box waiting to be finished. I will try and air abrasive clean it soon. The question is the tear drop center section intact. My cousin extracted some of the matrix with an air scribe but that area now needs to be excavated with the sand blaster.

The plate this fossil is on has another Cryptolithus with part of the cephalon and an imprint of that center tear shape.

See my previous post about other trilobite fossils found at this locality.

On the back of the plate are a number of graptolites (see picture above - photographed wet). See images from previously found fossils in Carroll County at this blog posting.

Cheirurus niagarensis Trilobite Fragment

Previously images of an unprepped Cheirurus niagarensis trilobite pygidium was shown (see this post).  Recently, the fossil was cleaned using a sand abrasion technique.  These pictures show the results. First image fossil is photographed wet to enhance contrast. Fossil was found in the Waldron Shale of Clark County, Indiana, USA. It is dated to the Silurian Period.

The second shows a before and after cleaning images of the fossil. When cleaning I wear a respirator to keep silicate dust from getting to my lungs. Just looking at these images brings the memory of a smell of the rubber face piece. It is interesting how smells can get associated with tasks one does during the day.

Cleaning fossils takes patience and some strategy on how to approach the fossil to clean it. I was a little too ambitious on the top of this fossil thus wearing off the top thorax sections with the sand stream. Still it is nice to see more shape and detail of this fossil fragment. The Waldron Shale is easier to clean since it is soft and you can see immediate progress at removing it. During my cleaning session, I went through 3 canisters of sand while working on maybe 10 fossils before stopping. Thanks to Kenny for letting me use his cleaning equipment and help with removing matrix with an air scribe.