Saivodus ctenacanthus Shark Tooth Fossil

This appears to be a Saivodus ctenacanthus shark tooth (cladodont) fossil. It was found in Crawford County, Indiana USA. Fossil dates to the Mississippian Period.

Thanks to Kenny for image.

Unidentified Coral Fossil from Harrison County Indiana USA

A reader of this blog, Christina sent me a image of fossil she found in Harrison County, Indiana, USA. I think it is a Syringopora sp. coral fossil. All the fossils I have seen from Harrison County date to the Mississippian Period.

It is quite a nice find, especially if more fossil detail can be seen once the matrix has been removed.

UPDATE: Mike Huggins in the comments section left a link to a similar fossil he found.  It is a "Upper Mississippian Syringopora in limestone of the (Meramecian/Visean) Hillsdale Limestone of southern West Virginia" https://www.flickr.com/photos/79475348@N03/14012502204/in/album-72157644301124792/

Experiments in Fossil Cleaning with Power Washer

Earlier in the year, I was cleaning with a power washer and thought, "what if I tried this on some of soil stained fossils?". Well, I picked out a few pieces: crinoid plates that had been underwater at Lake Cumberland for a long time and coral and brachiopod fossils from Devonian Period limestones around Louisville.

This first fossil picture shows one of the largest horn corals to ever exist called Siphonophrentis elongata (Rafenesque & Clifford, 1820). It is found in the Jeffersonville Limestone usually in pieces in the soil. The fossil shown is stained a reddish-brown. The other two plates are broken up crinoid stem plates with one showing pieces of a calyx. They were found at Lake Cumberland, Kentucky. They appear to have layers of lake mud on them that is fused to the silica fossils. I like these fossils in that they have bluish look to them.

The next two show after cleaning. The crinoid stem piece did the best. I am not sure there was much change on the crinoid plates.

This next picture is of a coral fossil and brachiopod plate. The second image shows the cleaned fossils. The coral cleaned quite nicely.