Sunday, March 31, 2013

Trimerus delphinocephalus Trilobite

I have now been collecting fossils in the Waldron Shale for several years and I have a short list of the rare fossils I want to find in my collecting lifetime. I call these elusive fossils the "Holy Grail" specimens. It is in reference to the King Arthur legends of his knights quest to find the cup Jesus used at the Last Supper. To me, a Grail fossil means a specimen that is extremely hard to find, if not impossible.

My "Holy Grail" Waldron Shale fossils to find are: intact prone position Bumastus trilobite, any type of blastoid, intact prone position Arctinerus trilobite, and an intact prone position Trimerus trilobite. While hunting with my young nephews (Perceval and Gawain, okay not their real names... joke), I almost achieved finding a Grail fossil.

Behold these pictures of an almost complete Trimerus delphinocephalus (Green, 1832) trilobite. It was fossilized intact but the tail (pygidium is missing and the front of the cephalon has broken off with the indentation left in the shale showing it was there at one time). Fossil was found in Clark County, Indiana in the Silurian age Waldron Shale. It has not been cleaned and photographed wet or partially wet.

It might not be that impossible to find this trilobite as I think, see one on the Week's trilobite web site.

Images taken with microscope of trilobite thorax sections.

Microscope images of scratch marks on thorax segment. Were they made when the trilobite was still alive? If so, by what?

Saturday, March 30, 2013

Lepidodendron? Coalified Fossil

This coalified fossil could be a decorticated bark of Prolepidodendron or Lepdidodendropsis from the Upper Devonian New Albany Shale. The New Albany Shale can be found around the southern Indiana and northern Kentucky. Usually when I find this type of fossil I think of it being an Archaeopteris or Callixylon.

I took these pictures at a local fossil study meeting. Thanks to Herb and Bruno for their opinion as to what this might be.

Saturday, March 23, 2013

Nummulite Foraminifera Fossil

This foraminifera fossil is known as a Nummulites laevigatus?. It was found near Soissons, Aisne, France. The fossil dates to the Eocene Epoch (about 47 million years ago). This fossil originally just a smooth disk about the size of an American dime. Using a belt sander, the surface was taken off revealing more spiral chambers.

Thanks to Dave for this fossil.

UPDATE on 2020/02/15 added species name.

Friday, March 22, 2013

Atrypa reticularis with lophophore

This fossil is chipped which revealed what looks to be its feeding apparatus or lophophore. The Silurian Period brachiopod is probably a Atrypa reticularis. It was found in the Waldron Shale of Clark County, Indiana.

Thursday, March 21, 2013

Calymene celebra Fossil

This Silurian fossil is a Calymene celebra. It was found in the Racine Formation of Milwaukee County, Wisconsin. Such nice preservation and it reminds of trilobites found in the dolomite around Bardstown, Kentucky.
Thanks to Nathan for the fossil.

Wednesday, March 20, 2013

Meekoceras Ammonoid Fossil

This ammonoid fossil appears to be a Meekoceras sp. It was found in the Thaynes Formation of Salt Lake County, Utah. It dates to early Triassic Period.

Thanks to Nathan for this fossil. Recently, he visited the Louisville area with a group of students from the University of Wisconsin and we exchanged some fossils. They were very dedicated and impressive in their fossil searching capabilities. We visited a number of local sites and collected for hours in the rain, sleet and snow. Brrr, it was cold and wet. Lots of neat fossils were found, including a Silurian cystoid, a spiny brachiopod, trilobite segments, a giant snail, colonial coral colony, and lots of ziplock bags of fossils. After Louisville, they had more areas to visit around the midwest to find fossils at.

Monday, March 11, 2013

Palmoxylon Fossil

This fossil appears to be of the genus Palmoxylon and was found in Texas. It is from the Eocene. Fossil was photographed wet and magnified 40x and 100x which is about 6mm and 1mm field of view.

Thanks to Herb for the fossil.

Sunday, March 10, 2013

Palmoxylon Fossil Magnified

These magnifications are from a thin slab of silicified palm fossil. I wet sanded the slab with 320 and 800 grit paper. Karate Kid's Mr. Miyagi would be proud of my sanding work!

Fossil was photographed wet to enhance the contrast. Have not tried polishing it yet.

This fossil appears to be of the genus Palmoxylon and was found in Texas. It is from the Eocene.
Thanks to Herb for the fossil.

Monday, March 4, 2013

Icriodus expansus? Conodont Fossil

Here is a freshly discovered conodont fossil found in the Beechwood Limestone of Clark County, Indiana. It is Middle Devonian Period in age. It appears to be an Icriodus expansus? conodont fossil.

Thanks to Kenny for the picture.

Sunday, March 3, 2013

Favosites Growing on Crinoid Stem

A Favosites coral growing around the stem of a crinoid. This type of growth appears to have been typical for this coral. Fossil was found in the Waldron Shale of Clark County, Indiana. It grew in the Silurian Period about 420 million years ago.

Below is an illustration from Plate 17 (Figure 9) Indiana Department of Geology and Natural History Eleventh Annual Report John Collett State Geologist 1881. It shows a Favosites coral growing on a Eucalyptocrinus crassus stem.

Saturday, March 2, 2013

Eurypterid and Mastodon Fossils at ISM

I am a big fan of museums which is why I have spent hundreds of hours volunteering at my local one. One of my favorite museums is the Indiana State Museum in Indianapolis, Indiana USA. They have a great number of exhibits showing off fossils found around the state of Indiana. In addition, they are publishing videos of fossils they have in their collection.

This first video is of a Silurian period Eurypterid found in a quarry in Kokomo, Indiana. If the display box is showing a different video, here is the direct link:

The next video shows the assembly of the 13,000 year old Fred the mastodon fossil for an exhibit entitled Indiana's Ice Age Giants: The Mystery of Mammoths and Mastodons. It opens in November 2013. If the display box is showing a different video, here is the direct link:

This video shows the Bothwell dig in 2005 that uncovered seven mastodonts, part of giant beaver, and vertebrate of stag moose. The dig was near Hebron, Indiana. See video at this link:
This video shows a 2008 fossil dig in an Indiana corn field.