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Being a Colorado native, I have taken multiple trips to the public-access Florissant Fossil Quarry located near Florissant Fossil Beds National Monument in Florissant, Teller County, Colorado. This quarry provides fossil collectors fantastic access to the shale layers of the Florissant Formation, a late Eocene (Priabonian, ~34 million years old give or take) lagerstatte known for its diverse fauna of fossil insects, in addition to plants, gastropods, and very rarely vertebrates. Most fossils occur in very thinly laminated ashy grey shales. Other lithologies present include well-sorted tan course sandstones and well-sorted grey claystones. A lacustrine depositional environment is apparent, and though the Florissant Formation has previously been interpreted as the remains of a single large lake (the retroactively named Lake Florissant), it is now generally thought that deposition occurred across several smaller lakes, which of course shifted in their exact location throughout the period of deposition. This thread is for me to share some of my better quality (or more interesting) fossil insect finds from the Florissant Fossil Quarry, and to allow other people to share their Florissant insects. I intend on updating this thread as I make more collecting trips. Most insect fossils found at Florissant are of poor quality, however exceptionally beautiful specimens do crop up quite frequently. Regardless, identification even down to family level is usually very difficult, and some specimens I even have difficulty assigning to an order. Additional reading: https://bioone.org/journals/palaios/volume-27/issue-7/palo.2011.p11-084r/DEPOSITIONAL-SETTING-AND-FOSSIL-INSECT-PRESERVATION--A-STUDY-OF/10.2110/palo.2011.p11-084r.short Please note that at least for now picture quality is not ideal. I do not have the capacity to take good quality macro photographs, but I am doing the best that I can. The scale of the ruler is millimeters, magnification (when applicable) is noted. Order Diptera (True flies): Probably my best-preserved Florissant insect (and one of the first ones I ever found). Another fly. I'd like to be able to identify this one to family (and it almost certainly is identifiable to family) but I haven't been able to place it. This is a gorgeous fossil! Magnified 20X under a stereo microscope. Another gorgeous fossil fly. Possibly a gnat (suborder Nematocera), but I'm not 100% on this identification. Partial fly of indeterminate family, most of the abdomen is apparently missing. Both wings are preserved, the thorax and head are also nicely detailed. This is an example of a march fly (Family Bibionidae), probably the most common insect at Florissant. Many specimens (such as this one) are preserved without their wings. The head and mouthparts are very nicely preserved here, I feel shameful that I could not manage a better photograph. Crane fly, (Family Tipulidae). The preservation quality is not fantastic, but the gross anatomy can be easily made out (both wings, the abdomen, thorax, head, eyes, and even the halteres and some of the legs are present). Order Hymenoptera (Bees, ants, wasps, and relatives): A nice solitary bee (clade Anthophila). The details are not as high-fidelty as some other Florissant insects, but a nice complete specimen. Order Hemiptera (True bugs): Magnified 20X under a stereo microscope. A shield bug (superfamily Pentatamoidea). This is a really neat specimen because fossil Hemipterans aren't particularly common. Indeterminate Order: A large insect that I've never quite been able to place. Two wings are very faintly preserved which would normally be indicitave of a fly, but this specimen just doesn't look much like a fly otherwise. The antennae are interesting, it's a very large insect, and the tibia has an interesting flange. Unfortunately I can't seem to get a good look at the mouthparts (which has been very useful for me in the past for identification). Magnified 20X under a stereo microscope. At first I thought this might be an ant (family Formicidae) but under magnification the shape of the head is more suggestive of a fly. Very poor preservation, I'm not confident I'll ever get a solid answer here. Larvae: A nice plump fly larva, looks to me to be from a botfly (family Oestridae) or a relative. A very strange fossil. The segmentation and tagmosis definitely means this is an arthropod of some sort, and an insect larva is my current interpretation. Still, I've never seen anything quite like it. I've had a few people suggest to me this might be the abdomen of an earwig, but that's definitely not the case (earwig cerci do not look like this or articulate with the abdomen in this manner). Non-Insect Invertebrates: Just an example of one of the tiny gastropods that are common. It takes a keen eye to see them, but once you can recognize them you realize they're very plentiful. If you have some fossil insects from this locality in your collection, feel free to post them here too! Cheers!

I'm interested in looking at the internal structure of fossils. I would like to try my hand at making thin sections. I found this protocol: Making thin sections by hand It looks feasible. I have microscopes and I'm willing to invest in some equipment as necessary. I would really appreciate hearing from anyone here who has made thin sections who could help me get started. Thanks Roger

So, I'm a bit conflicted. Part of me wants to call my specimen microfossils, yet another calls them macrofossils. Some definitions state the boundary as "being able to see the fossil with the naked eye", other state it as "being able to see the details of the fossil with the naked eye", and yet others state it as "being able to see the fossil with the naked eye or low-powered microscopes". On this forum the prefix "micro" is thrown - for want of a better word - around a lot, even when it disobeys official definitions (which are still incredibly ambiguous!). What do you guys think is the range typically associated with microfossils, and what do we use here? When will the world of palaeontology adopt consistent measurements and definitions across parties!? ps: yes that was a subtle dig at the inch / yard measurements at the end there!

I just recently came across a very helpful website: https://www.microbehunter.com/microscopy-forum It is a friendly site, and I’ve gotten quick replies to some very specific questions about a vintage microscope I recently acquired. There are a number of forums, including one for people looking to buy/sell parts. Some of the folks there have some pretty obscure old microscope parts if you ever find yourself in need of some. They’re also good for advice on how to setup and optimize your microscope.

On July 1st, 2021, I went for the first time to a public, personal site and was very pleased with the results of my fossil excursion. The locale consists of several exposed formations, namely the Liberty formation I was hunting in. In my region of southwestern Ohio, that's known to be one of the best fossil-hunting formations due to its remarkable preservation of particularly fragile Ordovician life, even when compared to the excellent fossil preservation quality of other formations in the area. The thirty-three degrees Celsius heat was rather hot by itself, and as the sun's rays made me question my latitude, the rainwater in the ground from the rain several hours prior was evaporating and creating a blanket of humidity-saturated air which prevented my body from transpiring. That was lovely. On top of that, this was above a very tall cutaway, so there was this constant updraft of hot, humid air coming from the bottom. Needless to say, conditions were extremely hot and humid. A thermos filled to the brim with refreshing, ice-cold cranberry-grape juice was a lifesaver, as otherwise I would have certainly overheated and becoming a sizzling omelet atop a frying pan of Ordovician fossils under that laser of a sun! With that being said, this is my first post regarding a fossil hunting trip in three years! While I have not been active on this forum, my paleontological trips have been ever more numerous. I remember you all, as I have been secretly watching in the meantime. I am a fossil sniper, after all. I should mention that I am an adult now, and I would prefer to have the "Youth Member" tag removed from my name. I plan to conduct a full survey of my entire collection before attending university, so look out for that. My collection is considerably sizeable now, having nine years of fossil-hunting under my belt. Here are my finds! Best & rarest for last, though all of them are incredible in their own right. Every edge of a square on the grid is half a centimeter. Assorted rugose corals. Gastropods. Branching bryozoan. The central branching bryozoan specimen in the prior figure under 200x microscope magnification. The skeletal cavity wherein individual zooids once resided 440 million years ago are evident, each 0.2 millimeters in diameter. The sheer level of detail in the preservation is as mind-blowing as this fossil's age. This photo is the product of using a computer to compile 140 photos focused at different layers of the specimen, as microscopes have a very narrow depth of field. I'm sure you all find as this fascinating as I do, so I compiled a photo for you guys. Assorted brachiopods, with two bivalves on the top left. I collected some superb Rafinesquina alternata, which don't tend to come with both fragile and thin halves intact, together, and out of the matrix. There were also some Leptaena that I did not photograph, but were lovely and undulating. The rest are common genera here, except for the fourth one from the right in the bottom row and the partial one of the same species immediately northwest of it, which I would like help identifying. Expect to see it soon on the ID forum. Assorted associated, straight-shelled nautiloid cephalopod septa. A larger example of associated, straight-shelled nautiloid cephalopod septa and a partial living chamber. Calcified straight-shelled nautiloid cephalopod. I always love the crystals on these. Flexicalymene meeki on the left and right. The left one is perfect, and is a very large example of what I generally find--my largest self-found complete trilobite, in fact--so I'm very happy with him. The right one is heavily weathered along its left and right, but the medial length of the pygidium, thorax, and cephalon are all present in some way, and the pleurae and glabella are resonant with Flexicalymene meeki, and I'm very happy with him, too. Adorable, curled little finger hugnuzzles of the ancient sea. Drum roll please! Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 This is a huge living chamber of a straight-shelled nautiloid cephalopod! Unlike the septal segments, the living chamber is very fragile with its thin, unsupported walls. This means it is very rarely preserved. Hence, in my near-decade of fossil hunting, I have never found a complete living chamber with its outer shell included until now. Let alone of this size! The only reason this one survived is because of the encrusting bryozoan that grew over its walls and thus strengthened them after the animal died--Figure 5 demonstrates the layers of the bryozoan well. This is also demonstrated on the side without bryozoan strengthening it in Figure 4, and how it simply crumpled due to the weight of sediments that accumulated on top of it after the animal died. Interestingly, one side has much more encrusting bryozoan than the other--this suggests that immediately after the animal died, part of the shell was resting on the silt of the ocean floor, preventing bryozoan from growing on it. The contrast in the thickness of walls of the living chamber & encrusting bryozoan growth on opposite sides of the fossil is evident between Figures 1 and 2, where in Figure 1 the walls of the living chamber are quite thin (one can tell from the thickness of the dark cracks on the bottom left), whereas in Figure 2 the walls are visibly significantly thicker (and layered from the encrusting bryozoan, upon zooming in). Deducing all of this is so cool. Additionally, Figure 3 zooms in on the bottom left fraction of the visible living chamber in Figure 2, and it actually shows the bryozoan growing around the edge of the living chamber walls and into the living chamber. This means that's the very outer rim of the living chamber! (In Figure 3, the white line is the living chamber wall, and the layers around it are the encrusting bryozoan. The light tan stone inside is just limestone.) On top of the sheer rarity of a fossilized living chamber, especially of this enormous size, having the edge of the living chamber preserved with enough detail to show the bryozoan that that grew into it over its rim—almost half a billion years ago—fascinates me. To finish this post off, there really is a mystery in every fossil. With the encrusting bryozoan only growing one side of the living chamber in the final specimen, and the subtle, hard-to-spot detail of how it grew around the rim and into the living chamber, it's like every fossil is a murder mystery (literally) and we have to be Sherlock Holmes and figure out details about how the animal died. Considering this was 440 million years ago, we're all some pretty hardcore forensic scientists!

Hi everyone, I have been collecting fossils for some time, but this is my first post in the forum. I've recently acquired a stromatolite slab from the Strelley Pool formation. I have access to a laboratory compound microscope, and I was wondering if there is anything interesting that can be seen under magnification. I understand that I probably won't be able to see microfossils of any sort in this magnification, but I'm just wondering whether there are any interesting/discernible structures. I have an image that I took via this microscope attached below, and I can see dark clusters and white flakes amidst layered brown bands. Are these ordinary rock inclusions or does anything indicate past biological activity?

So I make slides of microfossils from ~ <1mm - 2mm. I use a glue that I make with food grade gum tragacanth and water as was recommended to me when I first started. However, I have always found it a bit annoying to make, get the consistency right and keep properly, especially as I haven't been able to find any definitive guides to this. I'm wondering whether any of you use gum tragacanth as well and have a ratio/recipe/advice for me? Or if anyone has had good success (long lasting, dries clear, secure, fossil safe) with any other type of glue? Thanks!

I bought a pack of dinosaur bone rubble ( Sauropod allegedly) to make up the min price on a order of rock. Polished up a bit on my flat lap and did a fluorescence scan just on the endogenous fluorescence. Turns out to glow all over the shop and makes a great test slide . The microscope tracks a laser spot across the sample and measures the fluorescence produced at whatever wavelengths you set. The first image is one frame at higher res, the field of view is about 60 microns. but I was testing the frame stitching so the second image is a tiled scan - same res. The original files are 3d too though you can't get that far into a lump of bone with visible light. Any good targets likely to give me fluorescence in the microfossil world?

Hi! I recently acquired a bunch of microfossil samples for kids to play but did not expect them to be so small. We tried some microscopy but ended up applying a little trick that actually to helped to film them "in action", which was kind of cool. I do not know if this technique is a common knowledge or not but I decided to share. Perhaps, it will be of use to somebody. Here you go: Any suggestions for improvements? Thanks!

Hoping some of the pros here are willing to share microfossil prep techniques or suggestions to journal articles on the subject. I have been hunting conodonts and the like for quite some time, but the glacial acetic acid digestion and pan and scan techniques have failed me. I experimented with HCl and H2SO4 in various concentrations, and even tried some ion exchange extractions ( which work on paper, but are lousy in practice)! This sort of fossil hunting has become vendetta for me and I suspect I am using the wrong search terms in the academic data bases. I'll be on an excursion until the 26th of July, but I'm going to try and check in here from Spanish Fork or Delta. (And hopefully have some non-nebraska samples to work with and turn my students loose on!)

Hi everyone! I'm looking to buy a Stereo Microscope in Europe for microfossil observation and was wondering if anyone can point out recommended brands. The price range for me is <400 Euros. Thanks!