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For some time, I have been wanting to check out some of the lesser known formations that exist in my local area. The Devonian Mahantango Formation and the Needmore Shale are undoubtedly fun to explore and yield some beautifully preserved specimens - something that can be seen in a number of posts on this forum - but I still had the itch to collect from something a bit more obscure. That opportunity presented itself in the Ordovician limestones that expose intermittently in western northern Virginia. A small body of literature exists describing these formations and analyzing their fauna, particularly the silicified trilobites they are best known for, but they do not seem to be nearly as thoroughly explored as nearby Devonian formations. Armed with my trusty Estwing, an overly chipped chisel, and the hope of uncovering some silicified trilobites, I headed over to one of the better known Ordovician exposures in the Virginia area. This particular exposure is quite large and unique due to the different formations it exposes. The road cut begins beside a small stream (in which limestones can also be found) and is composed of large, white largely unfossiliferous limestone. This limestone represents either the New Market Formation or the Lower Lincolnshire limestone. As one moves rightward along the exposure, the white limestones continue for some time before grading into significantly darker limestones. These, which are part of the Upper Lincolnshire limestone, have been interpreted to represent the Taconic orogeny which took place in the Appalachian region during the latter part of the Ordovician period. The dark Upper Lincolnshire continues for an appreciable distance as one travels right until it eventually transitions to the Edinburg limestone. The Edinburg limestone, which is composed of alternating beds of limestone and shale, also represents a period of rather intense deposition caused by erosion of the mountains that had formed during the Taconic orogeny. The Edinburg limestone at the exposure appears white to dusky grey due to weathering, but, interestingly enough, when it is chipped, the true jet black coloration of the limestone is revealed. The sequence continues past the bounds of the road cut that I explored, with an exposure of the Martinsburg Formation - which is yet younger than the Edinburg formation - exposing not far from the road cut. Here are a few pictures I took of the road cut. Unfortunately I did not have a chance to take more pictures, and I am not exactly sure as to the specific formations each photograph depicts. I briefly explored the Upper and Lower Lincolnshire limestones, but I did not find much with regards to fossil content. Most of my exploration was focused on the layers of the Edinburg limestone, which I had heard were the most productive with regards to silicified trilobites. Unfortunately, I do not believe that I recovered any silicified trilobites from the exposure. However, I did manage to find some silicified brachiopods in varying states of preservation and a number of other interesting fossils that I have not been able to identify. Now, let's delve into some of the finds . Brachiopod 1: Brachiopod 2: Brachiopod 3: Brachiopod 4: Brachiopod 5: Brachiopod 6: This particular brachiopod previously had more of the (silica?) coating, though I believe I inadvertently removed it by treating the specimen with concentrated vinegar. I would not want this to happen to any other specimens, but Brachiopod 3 and some of the others would certainly look very nice if some more of the limestone/mineral coating could be removed. Would there be a way to do this without physical preparation techniques (I do not possess the proper equipment for this and even if I did, I would be afraid of ruining the fragile specimens)? Brachiopod 7: This was one of the best preserved brachiopods that I found, which was quite ironic since it happened to be exposed to the elements right on the surface of the limestone. The photographs are not the best and I can certainly take more if they are needed. Brachiopod 8: Brachiopod 10: There were more brachiopods uncovered... but I think that is enough for one post. Now for some interesting microfossil hashplates that I decided to keep. Hash 1: Under the Microscope: Hash 2: Hash 4 Here I have included some photographs of some specimens that I have not been able to readily identify. Any help in identifying what organisms they are and even what genus/species they could be would be greatly appreciated! Below each one I have included a tentative guess as to what each fossil is. Unknown 1: I believe that this may be a weathered brachiopod viewed from the inside of the shell. Unknown 2: An interesting feature of the limestone or perhaps a preserve fragment of an arthropod/trilobite carapace? Unknown 3: I would guess that this piece would have the same origin as the specimen pictured directly above. Unknown 4: Same as the previous two unknowns? Unknown 5: One of the larger and more interesting specimens that I found at the exposure. I am not at all sure what it is, though I would guess that it might be part of a graptolite or bryozoan. I'd be very curious to hear what others think about this specimen in particular. Unknown 6: Not at all sure what this is. To me it looks like it is a fossil, but it could very well be a mineral stain of some sort. Unknown 7: Upon first cleaning this specimen I thought that it might be a very weathered brachiopod. However, after inspection under the microscope it seems to me that it might simply be a mineral deposit or a geological feature. Unknown 8: An interesting piece of detritus found on the plate containing Unknown 5. Unknown 9: I would imagine that this is either an encrusting bryozoan, a sponge, or a fragment of trilobite cephalon. Unknown 10: Unfortunately I do not have a larger, better picture of this specimen. I will try to take another photograph of this one. I do believe that this might be some sort of fenestrate bryozoan. Although most of the specimens were smaller than those I am used to collecting, I was glad to have some interesting mysteries and to have the Ordovician represented in my collection. All of the micro photographs that I took were taken using a Celestron Microcapture Pro Microscope, which has been working phenomenally to view even some of the smallest fossils. I hope that you enjoy reading this post and I want to extend my gratitude in advance to any who help with identification of the specimens! (Edit: Not sure why these photographs keep appearing at the bottom of the post. Does anyone know how to fix this?)