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Hello, I'm struggling to identify what this trace fossil is and what its ichnofacies is! Please help and let me know what info you need!

Hi! Is this a stromatolite? I picked up this rock on the premises of the Teleajen oil refinery in Prahova county, Romania. I have seen a chert wedge in a limestone boulder once upon a time, but this stone is different. It has layers of chert and carbonate, right? I grinded and polished the stone. Here is a close-up from the carbonatic area (fizzles with acid): Any idea how old are these rocks when found in S-E Europe? Thanks!

I've never put much time into sectioned and polished fossils, usually just because I don't usually collect material that would look well cut over whole. While preparing a trilobite I collected in Illinois over the Summer and I was cutting sections off the matrix bottom so the matrix lay flat as a stand. To my surprise I ended up cutting thin sections through a Favosites coral that piqued my interest. Coincidentally, this was at the same time @FranzBernhard posted his thread demonstrating a low-cost approach to polishing and sectioning small carbonate rocks and fossils by hand. With such a handy guide put forward at a perfect time I decided to try my hand at sectioning and polishing fossils. I was waiting on grit polish in the mail for a while and that has now arrived which allowed me to finally try some sections myself. I figured I'd post the humble results here so as to encourage more people who might be interested in trying this. I've cut lots of rocks before but this was my first time attempting polishes. The uneven cuts from some of the specimens are noticeable in the polish. I tried to grind some of the surfaces even before polishing but this was more difficult for the hard material. Oh well. I think I can improve the fine polish on a lot of these by putting more time into them but I think this was good as a first attempt.

Hi all, I found these recently along Colorado's front range in the Niobrara Fm, about 20 mins southwest of downtown Denver. I am familiar with inoceramus, but these pieces have ridges - something I didn't think inoceramus had. They also have a similar cross-sectional structure with aragonite as the inoceramus fossils I've found, which makes me think it's some other type of clam or bivalve, maybe platyceramus? The largest piece appears to have small attached bivalves. Thanks for your help!

I suppose these are boring to most people but they have piqued my interest as of late, when I started noticing how many of them there are and how consistent their form. It appears as a trough-shaped thing made of carbonate, lighter than the surrounding black shales. These shales (Haslam Fm, Upper Cret.) are full of odd blobs and lumps and tube-shaped things that I have always ignored, assuming they were non-fossil, but they don't seem to work as burrows or concretions either, and considering the possibility of calcareous algae and the like, I started to wonder. (Do burrows ever have a U-shaped cross-section, and why would they have a lighter, calcareous appearance?) This one is not the best example, I need to pick up more when I see them, but hopefully you can see what I'm looking at. There are some lumpy, grainy shapes as well: Possibly a (sideways) U-shaped cross-section on the end here too but it is faint. Lots of variety of shapes aside from the usual roundish concretions, many nondescript but some recurring patterns among them such as the above. They all have a calcareous/carbonate composition (I assume from the lighter color). Any opinions? Biogenic or not? What would account for the formation of this long trough shape in particular? I will make a point of picking up more/better samples and add them here.

Hi folks, I found these specimens in a Permian dolomud/wackestone in central WY (Fremont County). It is from the Park City Fm. (Phosphoria equivalent). I've attached photos of two different specimens which were found about 10-15 meters from each other in the same bed. I found a few other examples, and they were typically spaced about that distance apart from one another (in other words, they don't seem to form colonies), and they were by no means common. These appear to be recrystallized (see macro images). As I said, I think this is a dolowackestone "matrix" and there appear to be some silicified (chert) burrows nearby to the specimens, for what that's worth. Up is stratigraphic up in the photos (photos are perpendicular to bedding, i.e. cross-section view). I can't find anything like this described in the literature on the Park City/Phosphoria, and I was hoping that someone with a little more experience in Permian fauna (e.g. the Capitan reef builders) or other might have some insight. I was able to collect one specimen, which I plan on cutting and polishing, and also making a thin section for a closer look. In the meantime, any thoughts on what I might be looking at?? Thanks very much in advance!