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Hi people, I have a query regarding the contents of some siderite nodules from a Duckmantian fossil forest site in N Wales for my PhD project. I had thin sections made of parts of several nodules and they all seem to have an abundance of 'faecal pellets'; rounded, often curved (banana-ish) shaped, mostly stratified pellets. These pellets have been replaced by siderite (FeCO3) and sometimes include pyrite and seem to have been the locus for early sulphate reduction by bacteria before conditions arose for the siderite precipitation. I've attached SEM images of the thin sections showing some of these pellets. We have only found a couple of fragments of crustaceans (Euproops I believe) and the host sediments were fine sands and silts. All the images show individual pellets with scale bars but "pellet5" is a zoomed out image showing the abundance of the pellets. They are all replaced by an Fe-rich siderite and are all quartz free. "pellet6" is different with a mottled texture and some potential apatite mixed in. Let me know if anyone has seen similar textures before and/or what could have made them! The palaeoenvironment was purely freshwater with meandering river systems, with a dynamic lycopod dominated fossil forest ecosystem. pellet3.pdf pellet2.pdf pellet1.pdf pellet5.pdf pellet4.pdf

The Rhynie Chert preserves one of the oldest terrestrial ecosystems, which is a hot spring environment. It's Lower Devonian, and the oldest know harvestman was also found there. These are some photographs of my thin sections from this environment. This first thin section is one of my favourites, it has several Aglaophyton major plants that contain fungal cysts of Palaeomyces gordoni, containing spores. These are more Aglaophyton major cross sections. In this and the one above, there are a few vascular bundles, these consist of thin-walled protoxylem cells, surrounded by thicker metaxylem cells, which is then surrounded by the phloem. In the cortex of some of these is the mycorrhizal fungi Glomites rhyniensis. Their hyphae look like a darker-coloured ring. These both are Aglaophyton major. This one has Aglaophyton major, as well as Retusotriletes spores and some more Palaeomyces gordoni cysts without spores. This section contains a few Retusotriletes spores. This has the plant Horneophyton lignieri in it, which had a rhizoids instead of roots. In the upper left of this one is an arthropod coprolite consisting mostly of spores. Lastly, this is a piece of the Rhynie Chert containing Aglaophyton major.

The photos presented here are thin sections of a single chamber of an Ammonite. I recently obtained some broken fossil pieces from "Rocks and Gems Canada " for the purpose of slicing them and making thin sections for viewing through a microscope. The first samples are from a Chambered Ammonite. The area of interest is the filling in the chambers. If I am lucky there will be crystal formation, but most of the time it is just fill. This is a web presentation of the photos below The first two photos are the whole Ammonite as I received it. Photo one is a camera snapshot. Photo two is a stereo microscope composite of the Ammonite. The following photos are 1) Polarized light, 2) Polarized light with a Dark Field filter in place. Photos three and four are a single cell of the Ammonite showing what looks like crystal formations. Photos five and six a 4mm segment of the chamber edge. Photos seven and eight show a 1mm segment of a chamber edge.

I am not entirely sure where petrified wood fits in the fossil domain, but here is a sampling of some thin sections I made from a sample from the Rock Shed.(http://therockshed.com). The sample was cut in four slices, two cross sections and two transverse sections. One of the cross section slides broke into several pieces when I used too much force removing it from the polishing holder. The petrified wood is not very birefringent so the photos were taken with Plane Polarized light. A presentation showing more images may be viewed at The wood fossil is from The Rock Shed Photos 3 and 4 are full size, approx. 26mm, scans of the transverse thin sections. Photo 5 is a full size, approx. 12mm, scan of a cross section. Photo 6 at 25x of a transverse section.

its been days I am looking for a good way to make a complete image of thin section, so we can have a very big picture but very useful for some tasks. actually I need to make an image processing software then process thins sections automatically. I know pretty much about software part. but still got problems for making very good image. 1- I tried very high DPI scanner and the results were simply not acceptable as we have very small microstructures inside some microfossils. the image is below: 2- I tried making lots of images with camera on microscope then stitch images together. the result is pretty good but changing position of thin section and capture image takes lots of time still we have stitching time too. this is the result: 3- I know we have some special devices for these cases but they are very high price and mostly suitable for universities not for personal uses 4- anyway maybe the only option is making a little machine that can automatically move the thin section on the microscope stage then automatically capture photo. so any suggestions guys? if something is not clear please answer. thanks

these thin sections shows Familly Soritidae from Eocene carbonates. with porcelaneous test they are mostly in close environments and lagoons

These photos are of a thin section I made from a Gastropod fossil I purchased from the Rock Shed. Initially, under plain white light the slide looked rather drab, but once the polarizers were put in place the fill matrix inside the Gastropod showed many coloured minerals. The photos are of a cross section of the middle of the Gastropod.

A thin section view of a Rugose Coral Dibunophyllum from the Carboniferous time, Sappington Formation, Montana Photo 1 the rugose coral Dibunophyllum Photo 2 the end from which the cross section was cut. Photo 3 a full scan of the thin section at 2.5x Photos 4 to 6 show cropped views of the thin section at 5x and 10x. HTML version

The microscope thin section photos are of a Rugose coral, Heliophyllum is an extinct genus of coral that existed predominantly in the Devonian period. This specimen came from Mejdovb, Morocco. The coral is from a group of Rugose corals sent to me by forum member CanadaWest.. The thin section slices of the coral clearly show where the softer parts of the coral were replaced by minerals. The specimen. Cross section and transverse slices. Selected area cross section details Selected area transverse section details.

The shark's tooth is the second in a series of thin sections I am making of fossils. The tooth is relatively small at 10mm x 9mm and the final thin section is not all that promising as a large print subject. After looking at the tooth through a magnifying glass I noticed what looked like serrations on one edge. Looking at the thin section through a microscope confirmed there is something akin to serrations. This presentation concentrates on that area of the thin section. Click on the photo to see the thin section photos. I have elected to use my web server instead of the forum because there are 8 photos. Photo 1 is the tooth before it was ground down to a thickness of 70microns with the area of interest marked. Photo 2 is a closer look at the serrated edge. Photos 3 to 8 are through the a polarizing microscope. Photo 3 is a 5x magnification of the area. Photo 4 shows the texture of the tooth above the serrations. Photo 5 is the same area with the full wave lambda plate inserted. Photo 6 is a magnified 10x. Photo 7 is 10x magnification of a seashell fragment. I added it because the texture of the seashell is quite similar to the shark tooth. Photo 8 is the textured area at 50x magnification. I have to admit I do not know a lot about shark teeth, but the selected area looks like serrations and the texture of the shark tooth is remarkably similar to a seashell. Can I assume shark teeth and seashells have similar composition?