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Looking for a recommendation for a Peace River guide.

Hey everyone! Towards the end of my time down in Austin, I collected a dozen or so bags of matrix across three sites that covered the Bouldin Flags (Cenomanian), South Bosque (Turonian), and basal Atco (Coniacian) of Central Texas. Over the course of the last 6 months, I have processed and tried to identify everything that my sieve caught in order to complete this project of mine. I’m sure there are plenty of errors within this amateur study, but I hope that the overall information it provides will at least be of some use to my fellow hunters who are looking for a centralized place to figure out just what kind of tooth they stumbled upon in their local creek. I know that, especially in my first year of fossil hunting, the seemingly endless list of shark names looked like a mountain too tall to overcome. Perhaps this report might just help to demystify that obstacle. There were many expected finds and some total surprises. I learned a lot myself from this whole endeavor and am excited to share what I found. Special shoutout to @Jackito and @LSCHNELLE for so kindfully sharing their fantastic sites as well as their expertise. This could not have been done without their help! Also, if you have found a species of shark not mentioned in this report from the Bouldin Flags, South Bosque, or Atco of Central Texas, feel free to leave a reply with a photo and some info on your specimen! Enjoy! Abundant (), Common (), Uncommon (), Rare () Bouldin Flags (Cenomanian) The Bouldin Flags represents the end of the Cenomanian stage of the WIS in Central Texas. It carries much of the typical “Woodbinian fauna” that is often associated with Cenomanian sites from across the continent. The formation is “flaggy”, tending to split into layers. Much of the formation can be devoid of vertebrate life, but now and then, extremely rich layers may crop up and yield an extensive diversity of sharks, bony fish, and even reptiles to collect from. Processing the matrix can be difficult. I tried to process only the softest material I could find from productive layers as the harder parts were sometimes almost solid pyrite or totally cemented into an unbreakable stone. Even the parts that are soft tend to carry lots of grit that are rough on the hands and fossils. Nevertheless, the Bouldin Flags has some of the most diverse shark and reptile fauna as well as the richest layers, making it well worth the effort of locating. The majority of the collecting for this formation was done in the Lower Bouldin Flags, however, specimens that also occurred in the limited Upper Bouldin Flags sampling will be marked with an asterisk (*=Upper BF) Lamniformes *Carcharias saskatchewanensis Together with Cenocarcharias tenuiplicatus, these species make up the two most abundant sharks teeth to be found in the Bouldin Flags. They are typically only millimeters in size and tend to separate well from the matrix without breaking. C. saskatchewanensis can be easily differentiated from C. tenuiplicatus by its absence of fine striations on the labial faces of the cusps and cusplets. C. saskatchewanensis and C. tenuiplicatus are distinguished from Haimirichia amonensis by their significantly smaller size. I have also seen this species referred to as Microcarcharias saskatchewanensis. *Cenocarcharias tenuiplicatus A common tiny tooth found in the Bouldin Flags. They are easily identified by the presence of fine striations on the labial faces of their cusps/cusplets. Now and then, they may have an extra pair of cusplets. Cretalamna catoxodon Surprisingly rare given how abundant this genus usually is in other similarly aged strata of Texas. From the entirety of my material, I only came across one identifiable specimen in the final batch. Unlike mature Cretoxyrhina agassizensis, these teeth have a single pair of pointed cusplets and are usually more gracile. Unlike Cretodus semiplicatus, these teeth are more gracile and lack wrinkling on the base of the crown and cusplets. C. catoxodon is a relatively newly defined species within the genus Cretalamna and, to my knowledge, the only one documented from the Cenomanian. Cretodus semiplicatus One of the most coveted shark fossils of the Eagle Ford is the fearsome Cretodus. These are some of the biggest and most robust teeth to be found and can be spotted quickly by their size and diagnostic wrinkled crown bases on both the labial and lingual faces. To my knowledge, C. crassidens does not appear until the Turonian. C. semiplicatus, unlike Cretodus houghtonorum, typically exhibits a U-shaped basal concavity and U-shaped crown base border whereas C. houghtonorum is more of a V-shape in both departments. Both typically have gracile cusps. In my hunting at the Bouldin Flags site, I found one perfect tooth and a single, large broken off cusp to another tooth. Cretomanta canadensis This is one of the most interesting teeth to be had in the Bouldin Flags. Cretomanta has been interpreted as a planktivorous filter feeder. These teeth are sometimes confused with rostral denticles of Ptychotrygon triangularis, however the oral teeth of P. triangularis were not found at all in the Bouldin Flags Site. In contrast, the Atco Site (more on this later) did produce many of these oral teeth. I believe this suggests P. triangularis is likely not the culprit for the pictured specimens. Additionally, Cretomanta canadensis is commonly listed in faunas of other Cenomanian sites. Fairly recently in Northern Mexico, an amazingly preserved ray-like filter-feeding shark was discovered and named Aquilolamna milarcae. Sadly, no teeth were preserved, making it impossible to confirm synonymy between Aquilolamna and Cretomanta, but nevertheless there is a suspected connection between the two which future discoveries may one day prove. *Cretoxyrhina agassizensis On the right are the juvenile C. agassizensis ("Telodontaspis agassizensis") Cretoxyrhina are always a welcome sight and not all that rare for the Bouldin Flags. These are some of the larger teeth to be had and are generally well preserved. They typically do not have cusplets, however some specimens may have poorly developed ones as Cenomanian Cretoxyrhina were still in the process of diminishing them. C. agassizensis is a chronospecies of the genus Cretoxyrhina, representing the time period of the Late Middle Cenomanian to the Early Middle Turonian. Throughout the sifting process, I came across small, thinly cusped and distally curved teeth that somewhat resembled the larger Cretoxyrhina teeth I had as well. In researching possible IDs for these teeth, I came across the species Telodontaspis agassizensis which seemed like a decent match. However, Siversson makes the point that this taxon seems to appear only in places where larger, more typical Cretoxyrhina specimens also occur. It would seem that the two genera are synonymous and these smaller teeth instead belong to juvenile C. agassizensis. *Haimirichia amonensis Medium-sized teeth that are extremely abundant in the Bouldin Flags as well as many other Cenomanian deposits of Texas. A decent degree of heterodonty exists and lateral teeth may have many pairs of cusplets. This species was previously known as Carcharias amonensis, however the discovery of a new and well preserved specimen showed that it possessed enough morphological differences to warrant the creation of the family Haimirichiidae. I originally misidentified these teeth as Scapanorhynchus raphiodon which appears to not exist in the Bouldin Flags. *Squalicorax sp. Squalicorax is one of the most abundant teeth present. They are easily identified by their unique shape that highlights their generalist diet. There is currently much work to be done in properly separating the species of this genus across the Mesozoic, so I will simply refer to all teeth found as Squalicorax sp. Ptychodontiformes *Ptychodus anonymous The most common Ptychodus teeth found in both the Bouldin Flags and South Bosque. P. anonymous can be distinguished from other co-occurring Ptychodus teeth most easily on the basis of having a defined marginal area where the transverse ridges will merge instead of bifurcating and running all the way to the end of the crown. P. anonymous is known to have two distinct morphotypes (Cenomanian vs. Turonian), both of which are represented in this post. The Cenomanian morphotype is common in the Bouldin Flags and are typically smaller and more robust than their Turonian counterparts (however my Turonian specimens are just as small as my Cenomanian ones). Another key difference in the morphotypes is that Turonian teeth have an apparent concentric ornamentation of the marginal area whereas Cenomanian teeth have no such feature. It is possible, in the future, these differences may lead to the creation of a new species between the morphotypes. *Ptychodus decurrens This larger specimen in the lower 3 photos was misidentified. I now believe it to be a P. decurrens from the Upper Bouldin Flags. Ptychodus decurrens is a low crowned tooth that is also numerous in this formation. Like Ptychodus occidentalis, the transverse ridging gradually bifurcates to the edges of the crown as opposed to terminating at a distinct marginal area. These teeth are often broad and have the ability to get quite large in size. The bottom specimen shown was originally misidentified as P. marginalis. I have taken another look and now realize P. decurrens is a stronger ID. Despite it being a fragment, I do not think the tooth shows signs of a concentric orientation of transverse ridges and instead seems to follow the hooked on one side and straight on the other ridge pattern more typical of larger P. decurrens. Also, I initially misidentified the formation the tooth came from as being South Bosque based on visuals alone. After getting the chance to process the matrix for micros, it shares much of the same microfauna with the Lower Bouldin Flags and has little faunal overlap with the South Bosque outcrop. I now believe the location to be Upper Bouldin Flags. Ptychodus occidentalis Ptychodus occidentalis is rarer in the Bouldin Flags than the other Ptychodus. They can be identified by the bifurcating nature of their ridges as they travel through the marginal area of the tooth to the edge of the crown. The crown height tends to be higher than that of Ptychodus decurrens. In comparison to P. anonymous, P. occidentalis generally possesses finer and more numerous transverse ridges. This species is also capable of producing some very large teeth. Ptychodus rhombodus is a smaller-toothed species that commonly occurs in the Cenomanian WIS that also shares bifurcating ridge features. It has been suggested, however, that these may represent a juvenile form of P. occidentalis. Orectolobiformes *Cantioscyllium decipiens Common little teeth that belonged to a Mesozoic nurse shark. The teeth look similar to Chiloscyllium, but have striations present on the labial face. Sclerorhynchiformes *Onchopristis dunklei Although not the rarest to find, Onchopristis dunklei represents an order of sharks that hardly seems to be found in the Bouldin Flags. This species tends to preserve both oral teeth and rostral teeth. The rostral teeth are quite iconic, being best known for the multiple barbs decorating its edge. These teeth are fragile and rarely collected in one piece. From the Lower Bouldin Flags, I collected a handful of oral teeth and broken rostral specimens. In my small sample of Upper Bouldin Flags material, I only collected one O. Dunklei rostral and it happened to be the single complete one in the collection. Hybodontiformes Indet. Hybodontiformes Only a singular specimen of a Hybodontiformes tooth fragment was recovered. I don’t believe enough is present to make a confident determination as to whether it belongs to Meristodonoides or some other genera. It has striations on both sides of the tooth and a slight curvature. Other Fauna Amiid? A single, tiny arrow shaped fish tooth was collected. It is difficult to confidently lay down an identification, but Amiid is a candidate for this morphology. Coniasaurus crassidens Coniasaurus crassidens may be found in the Bouldin Flags on rare occasion. Most commonly, teeth, jaw fragments, and vertebrae are found disarticulated amongst shark teeth and shells. Because of their position within the order Squamata, Coniasaurus vertebrae share many visual similarities with larger mosasaur vertebrae from younger strata such as the Ozan. Although Coniasaurus teeth exhibit heterodonty, most of their teeth have a characteristically bulbous shape that distinguishes them from all co-occurring sharks and fish (though anterior-most maxillary teeth may be quite gracile in contrast). While Coniasaurus seems to be restricted to the Cenomanian in England, American specimens cross the Cenomanian-Turonian oceanic anoxic event (OAE 2) and reach the Middle Turonian with some reports even further beyond. Enchodus sp. Typical of just about every Cretaceous exposure in Texas is the saber-toothed Enchodus. The Bouldin Flags is absolutely filled with them. The teeth are generally quite small and vary in shape. Most commonly, they are flattened and take on a recurved shape. Sometimes they may be conical and completely straight. They may be smooth or have striations. Pachyrhizodus minimus These are very small and resemble miniature mosasaur teeth. They are smooth around their circumference and have a strong distal curvature. Pachyrhizodus is a genus known for having relatively large heads, similar to modern Grouper fish. Protosphyraena sp. Protosphyraena was a genus of fish that heavily resembled modern swordfish. Their teeth are common finds all over Texas. They generally take on a flattened shape and bear two cutting edges. They can sometimes have a slight curvature or stay completely straight. The ones I collected were among the larger fish teeth found. Known but missing sharks Pseudomegachasma comanchensis Despite not having personally collected one, Pseudomegachasma comanchensis is known from the Bouldin Flags. Similar to Cretomanta, these sharks are suspected to have been the oldest elasmobranch planktivorous filter feeders. The lingual protuberances on these teeth are so large, they almost look like backwards root lobes. Ptychodus marginalis Ptychodus marginalis is better known from the South Bosque, but has been previously found in the Bouldin Flags, though it is on the rarer end as far as Ptychodus go. They can get large, sometimes to the size of a golf ball. P. marginalis is distinct from other Texan species of the genera in that its ridges go on to form concentric rings as they travel towards the edges of the crown.

Looking for someone in the Erie or Cattaraugus co. NY area to go fossil hunting with. I’ve put hours of research into potential sites and would love to bounce them off of a local familiar with the area. Would also be appreciative if someone could show me around the area. A few hours of travel is okay as well. There just seems to be a theme of posted streams or stream segments and I want to make sure I’m following the law.

Mostly sandstone from clallam formation WA. The fossils are flaky and the sand stone has many cracks threatening to break into pieces. I know it’s not the prettiest, but I was hoping to stabilize the matrix a bit as well as some of the more preserved shells to expose and highlight them a bit

I recently completed my first fossil prep. Woohoo! As a novice, I did a lot of reading and research; trying to piece together exactly what I was supposed to do. How exactly I was supposed to "prep" the fossil and what that process entailed. While I found a wealth of information here on TFF, and other avenues, that information took a while for me to uncover and assemble into something useful. Not that the information itself wasn't useful, but uncovering a bit of info would often cause even more questions to arise. Consequently, it sometimes felt like taking 1 step forward but 3 steps back at the same time. So here is a novice guide, written by a novice, for other novices. It is intended for someone trying to figure out how to get started in Manual Fossil Preparation. The following information is what I feel is the basics of getting started in prep work based on my observations, research, and very limited experience. A quick guide to help get someone started who has been wondering what to do, but hasn't quite figured out where to start yet. Hopefully this will open up the wonderful world of fossil preparation for a few more people. What is Fossil Preparation? Fossil Preparation is the name given to the process of cleaning and repairing fossils. Making them more presentable for display, and revealing more diagnostic detail for study and research. Preparation at it's most basic form, is cleaning. Simply using a brush with water could be considered preparation. However, when most of us discuss fossil prep, it typically involves removing matrix. There are basically 3 ways to remove matrix from fossils. Using hand tools is generally referred to as manual preparation. Using power tools that require an air compressor, or electricity, is referred to as mechanical preparation. The third option is chemical preparation. Which, as the name implies, is using chemicals to prepare a fossil. Typically by dissolving matrix. Most people use one, two, or a combination of all three methods. I chose to focus on Manual Preparation. In my opinion, it is the cheapest, easiest, and the most forgiving form to start with. This is where most people tend to begin their prep journey. The process is pretty much the same with mechanical means. The more aggressive tools just make it go much faster. Which can lead to quicker results, but also quicker damage if done improperly. I figured it was better to cut my teeth on the cheaper, slower option, then upgrade tools if I liked it. I typically see “starter kit” recommendations for mechanical prep in the $800-$1000 USD range. You may get by with spending a little less, but it will still cost hundreds of dollars to get going. I spent less than $50 USD on my manual prep “starter kit” and you can get by with spending much less. Chemical prep can work well, and can be fairly cheap. A gallon of vinegar doesn't cost much... but it can VERY easily damage the fossil if you are not careful and don't know what you are doing. Proper precautions will need to be taken as well. Most chemicals used in fossil prep pose some sort of health hazard. Also, not all chemicals will work in all situations. What tools do you need to get started in Manual Prep? Anything that is sharp and can dig into the matrix that you want to remove. Seriously... Anything! There are people on TFF who started prepping with a wood nail, drywall screw, a push pin, and even a steak knife! That being said, there are definitely tools that will make life easier. Listed below are ones that I found the most helpful and personally used. Pin Vise* Magnification Lamp Dental picks Razor Knife** Brushs Sewing Needles Scribes (Sometimes referred to as Scribers) Scratch Awls Water *A word on Pin Vises... These are handy little gadgets, who's name is somewhat of a misnomer. While they are very useful for holding pins/needles and the like, they are typically sold as small hand drills, and can come with an assortment of micro drill bits. You will not need these drill bits for fossil prep, and if you can find a pin vise without the bits, it will usually cost less. They are sold by many hobby stores, or can be found online very easily. Simply put, they are handles with collets or chucks, used to hold very small things.You don't need a pin vise, but if you do purchase one, I would suggest a range of 0-.125 (1/8) inches or 0mm-3mm. This way you can hold the smallest of needles, and things up to the size of a standard rotary tool bit. Which is 1/8 inch or roughly 3mm. What you put in your pin vise will vary depending on what you are prepping, but I found that a scrib(er) or engraving tip for removing bulkier matrix, and a larger sewing needle worked rather well. They come in double ended forms, or you can usually find them cheap enough to buy more than one for quick switching between tips if you desire. **A word on Razor Knives... These are also known as hobby knives and are commonly referred to by a brand name that is rather “exact”. I had read people recommending to use these and how great they were to have around. I thought “Why use a razor blade on rock?” I didn't fully realize their use in fossil prep until I actually broke down and tried it. The tip of the knife can be used similar to a dental pick or needle and can slide between the layers of rock to pick it away or split it. I found that it could also be used to sculpt the matrix around the fossil. Sure it will dull quickly, but replacement blades are cheap, and it actually cut and planed the soft shale I was working with pretty well. I am sure there are more uses that I need to discover. Very handy and cheaply purchased. So... How do you actually prep? Well... You remove matrix without damaging the fossil. Things can happen, but this is the ultimate goal. First you use a larger tool to remove the bulk of the matrix. Depending on the size of excess matrix, you may be using a hammer and chisel for this, or you may use something like a scratch awl. My first prep was on a brachiopod valve so the scratch awl method worked well for me. I used the awl to pick and scratch at the matrix. Removing as much as I could, as quickly as I dared. Use a brush to get dust and debris out of your way. I used a small paint brush. Something that puffs air or even a little water can also work. Once you start to get closer to the fossil you will want to use something finer. When I got down fairly close, I switched over to a smaller scribe tip. When I was right next to the fossil I started using the sewing needle and dental picks. When you are right up against the fossil you will want to be very, very careful. Hopefully their will be a small gap between the matrix and the fossil. You can slide a dental pick, sewing needle, or tip of a razor blade in this gap and pick away the piece. Lifting it away from the fossil will hopefully cause it to flake off. If the matrix is more “sticky” you may need to painstakingly pick it off grain by grain. OK. Now you know how to prep, but what do you actually prep first? My advice is...Don't start with a nice, expensive, rare, or scientifically important specimen. Don't grab the one that you have just been dying to see revealed and start poking at it. There is a learning curve to prepping. The concept is simple, but in practice it is difficult. You WILL mess up. Especially on your first try. It happens. The needle slips and scratches. That piece of matrix that looked like it was going to break away cleanly took a piece of valve with it. Practice. Build up your skills and technique, then tackle that nice fossil. Your results will be much better and you will be happier with the outcome. Also, don't grab that big hash plate. Get something small that will give you a sense of completion in a few hours. A hash plate may take 10s or 100s of hours to complete. Starting with a small piece will give you a sense of completion and a much needed reward for your hard work and first try. If you collect fossils, I suggest getting something that is common to the area. Something that you might even currently pass over because they are everywhere. If you purchase your fossils, look for the same type of thing. Something that is common and not too expensive. Something that is a dime a dozen. Maybe even a fragment of a larger specimen that isn't worth much monetarily because it is broken. I would also suggest something that is relatively simple. Something with a lot of bones and pieces might throw you for a loop. Here are some Tips and Tricks that I learned just in my first few hours of prep work. Take your time! This is probably the most important tip I can give. Don't rush it. This process will take hours, not minutes. Even on something small like a brachiopod valve. I didn't time my first prep, but it took at least 4 hours. If you are tired, stop and give yourself a break. If you are frustrated with a piece that just doesn't seem to want to come off, move to another section to work on, and come back to it later. Rushing and frustrations cause mistakes. Magnification is very helpful. I would even say necessary. I used a magnification lamp. The magnification and light combo worked great for letting me see what I was doing. Especially when working close to the fossil. I have seen others who use those magnifying visors, or even a microscope. Keep your tools sharp. It sounds crazy I know. You are pushing these things into rock, and they will dull quickly, but they do work better when sharp. There is a noticeable use of less force when using a sharp tool. To borrow a philosophy from knife use... A sharp tool is a safe tool. Good lighting is a must. This goes hand in hand with magnification. If you can't see what you are doing, you can't prep. Wear proper safety equipment. Dust and flying debris is a real hazard. Even when using a tiny sewing needle. I would wear a dust mask and eye protection at the least. Gloves for protecting the hands from the errant dental pick/needle tip may come in handy as well. Know the morphology and/or anatomy of what you are trying to prep. You need to know what you are trying to dig out of the rock and what it looks like to avoid damaging the fossil or digging into the wrong place. The pieces and parts may not be where they are supposed to be, because of the nature of the fossilization process, but you need to have a good idea of what you are looking for. I wet the fossil from time to time. This isn't always an option depending on the fossil and matrix, but in my situation it helped wash away dust, bring out detail so I could better see what I was doing, and softened the matrix slightly, making it easier to prep. Stone is like wood, it has grain. Look for it and use it to your advantage. Picking and poking with the grain will typically yield better results that digging across or against it. Some things are not worth prepping. There I said it. Sometimes things will take way to long to prep, or are too delicate. You need to realize, and be ok with the fact, that some fossils, or part of a fossil, is better left alone. I'm sure I'll think of something else after posting... I hope this quick little guide will encourage other novices to try fossil prep. It is an enjoyable and rewarding aspect of the fossil obsession. Seeing something revealed for the first time in millions (sometimes hundreds of millions) of years has a distinctly wonderful feeling. Thanks to all those who helped get me going with their comments and suggestions in various threads. A special thanks to those that I PM'ed and asked questions of. You know who you are. Your knowledge and expertise were invaluable and greatly appreciated! Comments, corrections, and constructive criticisms are always welcome! Best of luck! Here is a link to my first prep that I referenced...

Hi all. eBay is generally a good website for us to get fossil specimens as long as we do the proper research, and seek out reputable sellers. However, certain fossils pop up every now and then that are obvious fakes, and not every buyer is diligent enough to know so. What we can do is to report these listings. Believe it or not, sometimes they do get taken down. To begin, say you notice a fossil you know is fake. Click on Report Item on the top right, it's above the eBay item number. eBay takes you to another screen: Choose Listing practices > Fraudulent listing activities > You suspect that a listing is fraudulent Hit Continue, and you'll be given an item number. Hit 'Send Report'. You do not need to be a bidder to make this report. You'll know the report is made when you're taken to this new screen: Ultimately, the best practice if you shop on eBay is to do your due research. Ask the experts here; they are more than willing to point out when a fossil is fake. I've personally saved thousands just by helpful advice here. Also, if you notice any fake fossils, do us a favor as well by posting about it here, but do not mention the seller's name or identity; we are here to learn, not conduct a witch hunt. Good luck

Hello, I recently visited a Permian site near Waurika Pond and collected microfossils for my students to explore back in the classroom. Is there a guide to identifying these fossils out there somewhere or is piecemeal searching here the way to go. If not, I will be making the one page guide over the summer have it to offer. Any help on something simple for my elementary aged students would be much appreciated. IMG_0064.DNG IMG_0065.DNG

I threw together a guide to manual prep tools for one of my students who is interested in trying her hand at some peck and scratch work on fossils. Figure I'd share a version of it with yinze. (mildly edited to comply with forum regs) Manual Prep Tools- Earth Sciences Basic "starter tools" You probably have some stuff around your home already that will work for basic prep- large sewing needles, various nails and screws, and even old drill bits. Basically, if it is sharp and pointy, you can probably remove some rock! Hardened nails, like blued finish nails and masonry nails can be fashioned into finer points with a bit of grinder work. See also: Pin Vise (below) Another option is hobby knives, like an Exacto as there are tones of different disposable blades and hooks and such for them. Personally, I rarely use them for fossils as I tend to break off the fine points and need my blades for my models and such, however, if you got 'em, try 'em! Automotive gasket picks/o-ring picks Pros: Cheap and easy to get- any auction site or automotive parts store has them. ranges from cheap to moderately expensive. Available with thin, pencil like grips and heavy screwdriver like grips Cons: You get what you pay for, the cheap ones tend to be softer steel and prone to bending and breaking. Be ready to re-sharpen tips regularly. Lousy for hard matrix and may leave marks that rust later on. Dental Tools: Pros: Fairly easy to get consumer grade versions online. Range from cheap to pricey. Extremely fine points, but way require occasional sharpening. Cheaper ones tend to bend easily on rock. Cons: Real medical grade stainless steel dental picks (the best ones) may be illegal in some places as they are medical equipment and not intended for consumers. The best ones can cost a lot. Also very sharp and easy to stab yourself with... Dissection Probes (stainless steel) Pros: Affordable and relatively easy to buy online. Heavy stainless steel versions cost more, but have a variety of tip types you cannot get elsewhere that are very useful. Easy to resharpen and maintain. The blunt probes can easily be ground into chisel tips and quad points. Awesome for soft matrix. The spear point type are so useful! Cons: The cheapest ones are no better than gasket picks and are soft and prone to bending. Also, very sharp and easy to stab yourself with... Industrial tungsten carbide (tool steel) scribes Pros: A personal favorite for hard matrix and fine detail work. CHEAP. Large variety of styles from a pointy stick, to a retractable pen. Tips can be replaced and are cheap. Cons: Do not strike these with a tapper or hammer- the tip will shatter. Chisels: Pros: Excellent for removing big chunks. Good for small stuff too if you know what you are doing. Great for the field and the bench. Best ones are acquired through art supply stores. Cons: Buy carbide tipped chisels designed for stonework...many cold chisels are designed only for use on mild steel or masonry and are virtually useless for stone due to softer steel used. Heavy and you gonna need a variety of hammers. Also...expensive....but you get what you pay for. Specialty Chisels: There are special tool steel thin chisels designed for splitting shale. If you are a splitter and don't have a few of these, you are doin' it wrong! Pros: Specifically designed for splitting fossiliferous shale. Cons: Can be hard to source. Side note: You can make your own if you have access to a grinder and some "blue" spring steel. General Purpose Hammers: DO NOT USE A CLAW HAMMER. I say again, DO NOT USE A CLAW HAMMER. They are not designed or made to withstand meta on metal impact (like a chisel head). There are tonnes of brands and types, but a good quality ball peen and a few mini sledges will treat you right. Personally, I prefer the "deadblow" style, but wood handle and all steel are good too as you can get really small weights. Mallets: Trust me, having a mallet is really handy. Deadblows are my preferred (pictured above), but I also use a sculptors mallet...which once you learn how to use, will likely be the only hammer you ever use during prep. Don't laugh, but if you need to really wail on something, a bowling pin is awesome. Paint Brushes/chip brushes/wire brushes: Artist paint brushes are useful for all sorts of things, from removing dust to picking up small bits. I use a mix of synthetic and natural bristles Chip brushes are super cheap to the point of being disposable, but don't last very long if used wet. Also, 100% recyclable. a clay sculpting "feather" brush Pin Vise: This is a handy little item for holding, well, pins. For your purposes this can be regular sewing needles, large gauge needles, sharpened nails, etc. DO NOT over tighten the chuck. It will jam and ruin your tool. An Exacto type knife handle can double as a pin vise by changing out the chuck jaws with rotary (dremel) tool chuck jaws. Pros: Inexpensive and Easy to get most anywhere. However as with most tools, you get what you pay for. Often sold with tiny drill bits which are handy for lots of things. Cons: Thou shalt not over tighten thine chuck! Cheaper models have soft aluminum or brass ferrules which can be prone to breakage and thread stripping if over tightened. cheap version expensive version...designed for fine scale modelers...notice the chuck and ferrule are steel and nickle plate, rather than aluminum. Scratch Brushes also known as Wire Brushes including sculpture brushes: Cheap, easy to get, various types available anywhere! You will find lots of uses for these. (Also, old tooth brushes are handy...the kind without the rubber stuff in the bristles!) Pros: Many! Cons: Be careful! Brushes with steel bristles can rust and stain your specimen---stainless steel, aluminum, brass, and nylon are safer if you have humidity around! So, there is a brief overview of basic hand prep tools. Field tools and powered tools are an entirely different subject discussed well in other threads.

Hi everyone, some time ago I got this fossil tooth from a European collector, the only thing the seller was able to tell me is that it was a canine of a carnivore (quite evident) and that it had been found in the most recent sediments of the Linxia basin in the HeZheng area (corresponding to late Pliocene-early Pleistocene age). Intrigued by the fossil, I decided to buy it and find out what animal it was. The first thing to do (in addition to hoping that the seller has given you correct information) is to search for articles regarding the fossil fauna and the ecology of the area where the fossil was found. In my case I found a very interesting article by paleontologist Deng Tao (Character, Age and Ecology of the Hezheng Biota, 2005) who gave me an overall view of the variety of carnivorous mammals that characterize the fossil association. Then we move on to carefully observe the fossil, based on the curvature of the tooth this would seem to be a left upper canine. Another important detail is the presence of evident grooves on the crown of the tooth, this feature suggests that the tooth belongs to a feline. Which felines were present in the fossil fauna of the area? -Panthera palaeosinensis = one of the oldest known species of Panthera, but its relationship to other Pantherinae is still debated -Felis teilhardi = an enigmatic lynx like cat -Lynx shansius (Lynx issiodorensis) = an ancestor of the current lynxes, generally it had larger size and with a more elongated snout -Sivapanthera linxaensis (Acinonyx pardinensis) = ancestor of today's cheetahs, it could reach much larger dimensions. Then we proceed by exclusion, the tooth is too slender to be a tooth from Pantherinae and also too big (62+ mm) to be Felis teilhardi's. There are therefore two options, Lynx shansius and Sivapanthera linxaensis, here the analysis becomes more complex because it is necessary to obtain precise measurements of the tooth. Therefore, the length and width of the tooth (mediolateral breadth and anteroposterior length) are obtained. The height is not important because it can be compromised by wearing or possible fractures. Using a digital caliber, I obtained a length of 12.2 mm and a width of 10.1 mm (the measurements are probably inferior than the real dimensions because the presence of the matrix and the skull did not allow a correct estimation. Probably the tooth is larger by 1-2 mm). Comparing the measurements obtained with those reported in numerous articles, we can observed that the dimensions of the tooth are slightly greater than those of a large specimen of Lynx shansius while they fall within the size range (very close to the lower limit, see graph) of Sivapanthera linxaensis. To conclude, considering the underestimation of the measures, either it is a large lynx (unlikely hypothesis due to the lack of wear on the tooth) or it is a young specimen of Sivapanthera linxaensis. Thanks for making it this far, I hope this little recognition exercise of mine can serve as a little guide on how to go about trying to identify a fossil. Clearly, if someone has a different hypothesis or a different theory, they can explain it.

Hi all! I'm very new to fossil collecting, (I haven't even got my first fossil yet!) and I'm hoping to learn more about fakes so I can make an informed decision by myself. What are some good rules of thumb you experts go by? Thanks!

The Basic Dinosaur Egg Guide Many people often mistake a concretion for an egg, to help clarify what is a concretion, and what is a real egg, here is a guide. A quick overview with examples: How to spot a concretion: How are they different from eggs? A concretion is a rather common rock made of tightly compressed minerals. Typically, concretions are a smooth sphere or oval with little to no surface texture or just a few bumps. Often nearly a perfect sphere, sometimes more of an oval. In a concretion, there is no eggshell. If you cannot see eggshell then you do not have an egg. If it looks the same shape as modern egg, such as from chicken then you do not have an egg. Concretions may have fragments breaking off and these will tend to be smooth on both sides. They tend to be dull earthy colors with a different composition in the center, as seen by a change in color. A different color in the center normally means you do not have an egg. Often circular bandings can be seen around exterior of concretions. Sizes of concretions range from just an inch, or a few millimeters, up to more than 10 ft (3 m). Egg sizes, along one side, range from just an inch or a few millimeters and top out at around 8 in (20 cm). If you find an oval or round shape, which is larger than 8 in (20 cm) along a side then it is probably not an egg. For more information on concretions: https://www.priweb.org/index.php/education/education-projects-programs/earth-101/concretions http://tumblehomelearning.com/geologists-find-largest-dinosaur-eggs-in-the-world-another-fraudulent-fossil/ https://en.wikipedia.org/wiki/Concretion In video form: https://www.youtube.com/watch?v=B5IoyLEwkMY Example of concretions, these three were incorrectly given an ID as “dinosaur eggs” however they are clearly not: From Tumblehome Learning, link above Pseudofossils: There are some pseudofossils, which can have a similar appearance to an actual egg, right down to seeming like there are bits of eggshell. This pseudofossil does look similar to an egg and even seems to have eggshell, however it is not an egg and is actually geologic. The surface ranges too much in texture and composition. Pic from Montana State University, taken by P. Germano Trace fossils: Many times, an actual trace fossil can be mistaken for an egg, common examples of this are pupa cases and cocoons. As one can see below, they do tend to have an egg-like shape and are yet another perfect example of why shape alone should not be used when trying to identify eggs. The three below are important trace fossils, just not eggs. Pic by Tony Martin, Ph.D. How to spot a real egg: The best and only true sign you have an actual egg is eggshell actually being present. Eggs come in many shapes from a semi-rounded, elongated oval to a perfect sphere and many others. Shape is not a good indicator of an egg. It is useful but only when combined with other details. Eggshell often has surface ornamentation that gives it a unique texture which can be seen by the naked eye or with a hand lens. There are many such ornamentations and they are used to help distinguish one egg type from another. On the surface look for little bumps, ridges with valleys, river channels, and similar textures. Individual fragments of eggshell are rather common in some geologic formations so be on the lookout for a larger grouping of eggshell. From University of California Museum of Paleontology Also read: http://www.thefossilforum.com/index.php?/topic/59654-dinosaur-eggs-lowell-carhart-guide/ Examples of real eggshell: Example of eggshell fragments: An eggshell fragment from Maiasaura, which is the oogenus Spheroolithus oosp. Pic by W. Freimuth. Examples of real eggs: A clutch of Troodon formosus eggs, which are the oospecies Prismatoolithus levis. Pic from Museum of the Rockies Do I have embryos inside this egg? Most likely no. Embryonic remains are extremely rare within eggs, and you add that with the rarity of eggs to start and it is a remote possibility. No fossilized yolks have been found and since they are soft tissue, it is near impossible for any to fossilize. I still think this is an egg! If you still think you have an actual egg, then please start a thread. Take close detailed pictures with something for scale such as a ruler and provide all the information you can about it--like where it was found. Good pictures will help greatly with a proper and correct ID. Below is an example of how to best photograph an egg or eggshell. There is clear lighting, a background which is clearly different than the eggshell in question and a scale bar. Lights can be as simple as a desk lamp; a scale bar can just be a ruler and the background can be very simple, in the example just a paper towel. Megaloolithus egg. Pic from Montana State University, taken by P. Germano If you would like to learn much more on eggs, here is the advanced egg guide which goes in depth. Also, see the advanced guide for sources. Eric P.

I was curious if there was a visual guide to tiny (between 1-5mm) shark teeth from Florida? I’m almost done going through a bag of micro matrix and have found at least 100 very small teeth that I would love to identify without bombarding the forum with more questions than I’ll already be asking on other items I’ve found. I can usually tell what they are when they’re larger, but these tiny teeth are somehow more difficult to me. The area that the matrix came from was described as a shallow bay that would have served as a nursery for sharks and other aquatic animals, so I’m guessing that they may be juvenile teeth? I would appreciate any help I can get here so I don’t have to constantly ask you all what shark a tooth may have come from, it’s really in the forum’s best interest here.

Does anyone have a legit guide for sharks teeth they would like to share? I have thousands and want to organize the mint ones. I've searched online for guides, but there are way too many that are incorrect. I'm spent on searching and would just like something 100% I live in Venice Florida if that helps. Thank you Brandon

HI all! I am excited to get to go back to Venice Florida tomorrow for a whole week. I was wondering if there was a good fossil guide who could take me out hunting - something a little more advanced than just "beach finds". However, I'm not into scuba or snorkling. (not that I don't enjoy that, just not right now). Any suggestions? Thanks!!

Hello dear fellow forum members, I have to admit that until recently, the fascinating diversity of Trilobites escaped my closer attention. Now, triggered by @Kane s beautiful drawings and @rews Trilobite of the week I decided to take a closer look at some of what I had in my showcase for many years simply as "trilobite", my (everchanging) focus being more on vertebrates. By looking at a lot of pictures I decided the two rolled up specimens below should be Phacops to the left and Hollardops ("Metacanthina") to the right. Then I found a pic of Gerastos, which to my untrained Eye resembled Phacops quite a bit. And then I learned that Gerastos is not even a Phacopid, but a Proetid. So here is my Question: How do I find out what order of Trilobite I am looking at before searching for finer cladistic resolution? Or is that not a helpfull approach due to high diversity inside the orders, maybe convergent features...? I searched the Forum but didn´t find a basic Trilobite guide, if there is one I´d gladly follow a link. Thanks in advance, J

Hi I decided to make a quick guide on how to ID Tyrannosaur teeth from the Belly River Group of Alberta, and the Judith River, Two Medicine Formations. I got this information on a study on how to ID isolated Tyrannosaur teeth from Dr. Angelica Torices. I’ll start off on saying Albertosaurus and Gorgosaurus are extremely alike not much differences in the morphology Daspletosaurus is a little bit Different, the morphology of these two Tyrannosaurs (Gorgosaurus and Daspletosaurus) are probably do to similar evolutionary history Gorgosaurus could of been Albertosaurus ancestor. Now I’ll tell you how to tell these two Tyrannosaur teeth apart (Gorgosaurus and Daspletosaurus). Gorgosaurus has two denticles (serrations) per mm where’s Daspletosaurus does not. Albertosaurus also have two denticles per mm because of Albertosaurus and Gorgosaurus evolutionary history. Also one more thing only with Albertosaurus, juvenile teeth can be different not just in there size but in there morphology too to the Adult teeth where’s Gorgosaurus and Daspletosaurus juvenile and adult teeth always have the same morphology. And thats what I’ve learned about this topic hope it helps, enjoy!!.

Hi all Im looking for advice for resources for identifying Insect and plant inclusions in burmite, or similar aged amber. I am open to purchasing or using online resources. They originated in Hkamti and Tanai , Kachin, Burma.. Ive got about 25 pieces that Id love to work on, and my google-fu Has been been failing to turn up much, although I have some plans to do some more generic insect family studies. Ive got a usb microscope for taking close ups, and will eventually learn how to stack images for better quality. In case anyone's worrying the pieces passed the Electrostatic and saltwater tests. Please enjoy this picture of a neat little gastropod I found in one of the pieces Thank you all for your time.

The Advanced Dinosaur Egg Guide Please share this with those who have egg questions. When possible, technical terms were avoided or defined. Every effort has been made to ensure accuracy, but it is always important to do your own research. This guide is merely a snapshot of information taken from many scientific publications. I am not an expert on eggs, rather I just love sharing what little I have learned over the years, what science has learned over the years. For an overview on how to spot a fossilized dinosaur egg and the sizes of eggs, see the basic guide: Somewhat outdated yet still a good overview of dinosaur reproduction and eggs, with a focus on Mongolia: What is so special about eggs? The amniotic egg is one of the most significant evolutionary adaptations as it allowed vertebrate life to permanently exist on land. Long before the dinosaurs and their modern descendants including the chicken, the egg came first. In fact, the better question to ask is “Which came first? The lizard or the egg?” Before the amniotic egg, amphibians and some fish were the only vertebrates able to even venture on land and only for rather short periods of time. A great deal of information has come from studying eggs. What we have learned is summarized as: From University of California Museum of Paleontology Egg Anatomy: Using the best known modern avian dinosaur, the chicken--scientifically Gallus gallus, let us go over the different parts of an egg: “(A) The generalized anatomy of an egg. (B) The chicken eggshell comprises three crystalline layers, including the mammillary layer, prismatic layer, and external layer. The cuticle layer overlying the calcareous eggshell is further divided to two layers, including a HAp inner layer and a proteinaceous outer layer. The shell membrane, namely membrane testacea, is also characterized by two layers. (C) SEM image of the cuticle on the surface of the Gallus eggshell, showing a patchy and cracked pattern. (D) SEM image of the radial section of the Gallus eggshell. The white arrow indicates the cuticle layer that lies on the calcitic eggshell.” From Yang et al. 2018 Fig. 1 Those were technical terms, so how about we simplify. The chicken egg has three distinct shell layers mainly made of calcite, then a soft membrane on the inside of that. What is known as egg whites are the albumen which surrounds the yellow yolk located near the center. The embryo develops within the albumen and is fed with nutrients stored in the yolk. The surface of eggshell is full of openings, tiny pores, and these allow for gas to pass through the shell. A developing embryo needs to breathe just like any animal. Additional information: http://www.ucmp.berkeley.edu/science/eggshell/eggshell1.php How to spot a fake egg: First, the best way to avoid fake eggs is to go and collect them yourself. Always make sure to follow the laws and have permission to collect. In the United States, typically a good way to follow the law is through collection on private land with expressed permission from the landowner. Views of paleontologists do range on private ownership of fossils with many not condoning or endorsing. I personally have little issue with it since amateur collectors have made countless important finds while prospecting for their personal collection. If you are going to buy, do everything possible to ensure the egg or any fossil was legally collected. Often with fake eggs everything seems too perfect. Eggs are delicate and easily crushed or damaged so if there are no signs of any damage or natural alterations be very wary. If the surface has ridges, check to see those ridges continue across a crack or break of the shell. Many fake eggs are mosaics made up of real eggshell fragments assembled together in an egg shape. These mosaics tend to not have the eggshell match on opposite sides of a crack. If you would like more information beyond what is provided or have an unanswered question, feel free to start a thread. If after reading, you want to purchase an egg then please ask the seller for the best pictures they can provide of that egg with something to show scale such as a ruler and start a thread. There are many on the forum who are happy help determine if an egg is in fact real. Just please, whether collecting or buying, make sure you know the laws and follow them. A few good threads on real vs fake eggs: http://www.thefossilforum.com/index.php?/topic/69391-examples-of-commonly-faked-dino-eggs/ http://www.thefossilforum.com/index.php?/topic/83533-red-flag-on-hadrosaur-egg/ http://www.thefossilforum.com/index.php?/topic/71462-beware-of-hadrosaur-eggs/ http://www.thefossilforum.com/index.php?/topic/79465-this-is-how-realistic-a-fakereplica-oviraptor-egg-looks/ How are eggshell and eggs classified? Many people try to name an egg to a specific dinosaur, usually incorrectly. With embryonic remains, however, an egg can be scientifically linked to a particular dinosaur (explained in the next section). Another accepted way for eggs to be linked is through a pregnant female, there are examples of females which died while carry eggs internally. Adults on top of a clutch can be used however only with caution. Eggs are given their own naming scheme just as animals have theirs. In normal taxonomy, we have species, genus, and family whereas eggs have an oospecies, oogenus, and oofamily. The term used for egg taxonomy is parataxonomy. Parataxonomy is used in place of traditional taxonomy when an actual animal or plant cannot be linked, for example--from a lack of data. In the case of Troodon formosus, its eggs are the oofamily Prismatoolithidae, oogenus Prismatoolithus, and oospecies levis. Parataxonomy is the same system used for trace fossils, such as footprints which are normally not linked to the dinosaur who made them. What is inside a fossilized egg? Is there a yolk? What about bones? Very rarely are embryonic bones found, typically eggs have been filled in with sediments. These then lithify (become rock) and so the inside of nearly all fossil eggs is rock that is similar, if not identical, to the surrounding rock. Eggshell is brittle by its nature and so often cracks, these cracks allow whatever sediments are surrounding to fill in the egg and, depending on how recent it was laid to said crack, allow the amniotic sac and other fluids to drain out. Here is a CT scan of some eggs I am working on. You can see how the surrounding rock is very similar to the inside of the eggs. In addition to looking for embryonic material, the scan gives us information on the infill, the true shape of the eggs, and reveals anything which could otherwise not be seen within them. Sometimes insects can be found near an egg, for example. Embryonic bones from the oviraptor Citipati, this embryo is curled within the egg. From Wikimedia Commons Importance of Embryonic bones: https://youtu.be/cubdagTiRHE?t=48 Embryonic remains are vital for an actual animal ID, so any chance of them being present must be investigated. If you have any tiny bones which can be seen inside an egg or directly near it, I would strongly encourage you to take the specimen to your nearest paleontology related museum or university. If it does have embryonic remains in or near, then the specimen is invaluable to science. The presence of those tiny remains allows for the next question to be asked. Do we know who laid this egg? Which particular dinosaur? Most likely no, there are some wonderful exceptions though. Several ootaxa (eggshell type) are known to the dinosaur genus or family they were laid by. Here are some examples of eggs and eggshell which were linked scientifically to a particular dinosaur from embryonic remains. Dinosaur or family and its known egg type, oogenus or oofamily. This list is not comprehensive as new discoveries and revisions are made every year. Allosaurus sp. known to Preprismatoolithus coloradensis. (This is debated) Beibeilong (Oviraptor) known to Elongatoolithidae. Citipati (Oviraptor) known to Elongatoolithidae. (See the picture above) Gobipipus (Avian) known to Gobioolithus minor. Heyuannia (Oviraptor) known to Elongatoolithidae. Hypacrosaurus (Hadrosaur) known to Spheroolithus oosp. Lourinhanosaurus (Theropod) known to cf. Preprismatoolithus. Maiasaura (Hadrosaur) known to Spheroolithus oosp. Oviraptorid known to Elongatoolithidae. Therizinosauroid (med to large theropod) known to Dendroolithidae. Titanosaur (Sauropod) known to Megaloolithus patagonicus. Troodon (small Theropod) known to Prismatoolithus levis. Generally, be wary of any claim that an egg was laid by a certain dinosaur! Additional information: http://www.ucmp.berkeley.edu/science/eggshell/eggshell3.php What groups of dinosaurs do we have eggs for? The vast majority of eggs are from non-avian theropods. This group includes dromaeosaurs (like Velociraptor), allosaurs, and tyrannosaurs. We also have eggs from Mesozoic aves (birds), hadrosaurs (duck-billed dinosaurs) and sauropods (long-necks). It is worth noting when we say that the majority of eggs are therapod we mean it. Around 61% of the eggs found globally are therapod and between 41-64% are maniraptorans (birds and their closest non-avian dinosaur relatives). For the others the numbers are much smaller: 7% are sauropods, 13% are ornithischians (hadrosaurs and relatives) with 19% still unknown and that is no yolk. Here is an example of a clutch from an oviraptor, elongated eggs are typical of many theropods: Pic from The Zuhl Museum On the non-dinosaur side of things, we also have eggs from turtles, crocodiles, lizards, and pterosaurs (flying reptiles). There are several groups of dinosaurs who have no egg representation in the fossil record yet. Despite many people trying to find them, there are still no ceratopsian (horned dinosaur) eggs. There are no ankylosaur (armored dinosaur) or stegosaur (spiked/plated dinosaur) eggs as of yet either. This could simply be due to bias in the fossil record but there also could be other factors. Perhaps, it is a case like the ichthyosaur (marine reptile), which gave live birth, unlike most reptiles that lay eggs. Most of us are familiar with the platypus in the mammalian world, which lay eggs despite being a mammal. Maybe some dinosaurs did not actually lay eggs. Now that would be an eggciting discovery! Below one can see how similar clutches are for two very different types of hadrosaurs. The above is a rather typical egg clutch for a hadrosaur with spherical shaped eggs. Some of these eggs had embryonic remains which allowed them to be identified to a dinosaur. In this case they were narrowed down to within the lambeosaurinae subfamily but sadly could not be narrowed further. Pic from Museum of the Rockies Clutch of another hadrosaur, the good mother Maiasaura. Again, the eggs are spherical and embryonic remains allowed the eggs to be linked with Maiasaura. Pic from Museum of the Rockies The great identification mistake: Now that it is abundantly clear the only way to link a dinosaur and an egg is with embryonic bone. Why is that? Surely there must be other ways to ID who an egg is from. Well, let me share the story of poor Oviraptor, who was wrongly accused of stealing eggs. When the first Oviraptor was discovered, the skeleton was not alone. Underneath it was a clutch of eggs. At the time there were no embryonic remains in these eggs, so it was assumed that the strange looking animal was, in fact, stealing the eggs from Protoceratops, hence the name oviraptor meaning “egg thief.” Later, not far from the original site, another nest was found, this time with an almost perfectly preserved embryo. The embryo was clearly of that of an Oviraptor to be eggs-act. So, with both discoveries, paleontologists determined that Oviraptor was actually a brooding dinosaur much like birds today. This story is an eggcellent example of science improving upon itself and the need to be careful with assumptions. Paleontology is an ever-changing field, which constantly works to improve our understanding of the prior natural world. A common incorrect identification nowadays is that of “Tarbosaurus eggs.” Tarbosaurus is very similar to Tyrannosaurus rex, however, it lived in Asia. Among the largest of eggs ever found, were two measuring 11 cm (4.3 in) wide and an amazing 60 cm (24 in) long. The elongated shape meant they were probably from a large theropod and so were thought to be from Tarbosaurus. Scientifically these eggs are the oogenus macroelongatoolithus. Based on detailed analysis, these eggs most likely are from a large oviraptor and not Tarbosaurus. Alright, so then how are eggs differentiated and how without embryonic bones would an egg likely be from an oviraptor? How are eggs distinguished from each other? We went over how to link a dinosaur to an egg, what about one egg to another or finding differences between eggs? Well, there are a few different ways, one is the surface of eggshell. Many eggs have different textures but surface texture can be eroded or altered so cannot be used alone. Thickness and porosity of eggshell can be measured and provide solid data points for comparisons. Two of the best techniques for examining eggshell are with the use of SEM and thin sections. A scanning electron microscope (SEM) is a very powerful microscope, which can view objects in eggstreme detail. Petrographic thin sections are tiny slices of a rock so thin that light can actually pass through it. Both SEM and thin sections allow for the tiny details of eggshell to be visible, meaning unique traits, variations, and similarities can all be seen. Below are two types of eggshell, how many differences can you spot? A thin section of hadrosaur eggshell, there is only a single continuous layer. Pic from University of Calgary A thin section of oviraptor eggshell, there are two distinct layers with the arrow showing the point where both meet. Pic from University of Calgary On thick eggshell, the cross-section view can often show many details otherwise too small to see. Below is Faveoolithus eggshell, which is large enough to show the internal structure of the shell itself. Pic from Montana State University, taken by P. Germano Naming: Dinosaur eggs, much like actual dinosaurs, are named following a convention with information in the name, and normally an honor to an individual or location where it was discovered. As already covered, naming uses a system of parataxonomy and with eggs, this is called ootaxonomy. Using the method covered above, similarities and differences of eggshell can be identified. Based on these similarities and differences, eggs can be grouped. Some of these groups are associated with a type of dinosaur. As already covered, from embryonic remains or other methods an animal can be linked and associated to its eggs. Sometimes eggs can be grouped based on similarities yet there are no ways to associate them with a dinosaur, so these are listed as unknown. An egg group being associated to a type of dinosaur does not mean all eggs within the group are exclusive to that single type of dinosaur. Some eggs were named prior to the naming convention being established or do not fit any of the known groups, as such these have a truly unique name. That said, most eggs fit one of the following: Name- dinosaurs associated Sphero- Hadrosaurs Ovalo- Unknown Faveo- Unknown (Could be sauropods) Megalo- Titanosaurs Dictyo- theropods Dendro- Therizinosaurs Elongato- Oviraptors Prismato- Troodontids Egg and dinosaur associations, from top to bottom, Elongato- with Oviraptors, Sphero- with Hadrosaurs, Prismato- with Troodontids, Dictyo- and similar eggs from unknown theropods. Pic from the Royal Tyrrell Museum What time periods do we have eggs from? Nearly every egg from the Mesozoic is from within the Late Cretaceous. One study found of 238 eggs examined, 225 were from the Late Cretaceous, 10 from the Early Cretaceous, 2 from during the Late Jurassic and a single egg from the early Jurassic. Since then more eggs have been found, yet the trend holds. A likely explanation for such massive bias would be the Late Cretaceous is more recent so eggs from then are more likely to be preserved and undergo less alteration. Did an egg hatch? The hatching question is a difficult one to answer scientifically with most egg specimens, of course, a nearly complete egg is likely unhatched. Much of the strength in eggs comes from their shape and this means once there is an opening in the shell that strength is lost. There are many ways for an egg to break, one of which is the baby breaking out, but many of the broken eggs we find may have yielded no baby. The term unhatched and failed are often used interchangeably but the term failed is preferred as “unhatched” which implies the egg was fertilized and had a real chance. It is possible and likely probable that no fertilization was the cause for many eggs to not hatch. An overview of the different ways an egg can be filled. From Mueller-Towe et al. (2002) Nest? For as rare as eggs are, finding an egg clutch within a sedimentary structure is many times rarer. There have been several sedimentary structures found around egg clutches, which were interpreted as nests. One of the most interesting of these is a “U” shaped structure which looks similar to a horseshoe, see the picture below. In the center of this “U” shaped structure was a clutch of Troodon eggs. It is possible many nests were constructed like modern bird nests, with sticks, straw, leaves and other such material. This material in nest building, unfortunately, means they would most likely not preserve. Possible nest structure for Troodon, tape measure equals 1m (39in) and the white plaster jacket is covering a clutch of Troodon eggs. Modified from Varricchio et al. 1997 How can we tell what happened to an egg and the nest? By studying modern nests, it was found eggshell fragments tend not to travel very far while remaining in large concentrations. This means when a large grouping of eggshell fragments are found, it is unlikely they have moved much. Modern eggshell fragments can be found in ratios of concave up vs concave down based on what happened to the nest. For example, if a nest had a predator come and eat eggs, the eggshell would be concave up vs down in a ratio of about 70:30, sometimes 65:35. Obviously, if the eggshell fragments are moved then ratios will not work, but again, where high concentrations of eggshell are found, there was little to no movement. The ratio technique is still in the early stages of being applied to nest from the Mesozoic so in time there may be more information. The Emu eggshell above is concave-up. Pic by P. Germano The Emu eggshell below is concave down. Pic by P. Germano In both pictures, different layers of the eggshell can be seen and such layering indicates the eggshell is from a theropod, in this particular case, an avian. Where in the world are dinosaur eggs found? Eggs are extremely rare and there are only a select number of places where they have been found so far. Eggshell fragments, on the other hand, are actually rather common and can be found in many formations. One main reason eggshell is relatively abundant compared to complete eggs is that a single egg when broken can become dozens of fragments. Geographically eggs so far were found in Argentina, Canada, China, Columbia, France, Great Britain, India, Kazakhstan, Mongolia, Peru, Portugal, Romania, South Korea, Spain, Switzerland, the United States, and Uruguay. Within Canada, eggs are exclusively found in Alberta. Within the USA, eggs have been found in Colorado, Idaho, Montana, New Mexico, South Dakota, Utah, and Wyoming. The vast majority of eggs are found in Asia. Additional information: http://www.ucmp.berkeley.edu/science/eggshell/eggshell4.php Did dinosaurs care for their young? It seems that many dinosaurs did in fact care for their young. Evidence for this has been found on multiple continents. There is still debate over the type and amount of care the parents may have provided. There are two major variations in care being debated, and these come down to whether the offspring were altricial or precocial. See the list of terms near the end of this guide for definitions. One possibility is that a group of adults would use cooperative breeding to care for a clutch, this is basically the village raising a child approach. With theropods, in particular Oviraptor, the presence of adults on eggs does support incubation and possibly even brooding. Hatchlings have been found within a nest and could have died there for many reasons, brood reduction and siblicide are both entirely possible. Given the diversity of dinosaurs, it is likely different dinosaurs provided varying levels of care for their young. Modern example showing a female crocodile providing care: Modern example of a spoonbill bird raising young: Some dinosaurs such as the sauropod titanosaurs, likely did not care for their young but rather used the same strategy as sea turtles. A large group of females would lay hundreds of eggs at once to overwhelm the predators and just by sheer numbers allowing some of the babies to live to adulthood. Are there any diseases or mutations of eggshells? Yes, we have paleopathologies found in eggshell. Paleo meaning ancient and pathology being the study of diseases, so paleopathology is the study of ancient diseases. One of the more common is where two or more layers of eggshell overlap in a way where the pores no longer pass through the entire shell, this reduces the amount of oxygen an embryo can receive. Too many of the pores being misaligned can be fatal. What color were eggs? One of the most recent breakthroughs in egg research is an ability to determine colors present within fossilized eggshell. Interestingly, from the eggs so far examined there seem to be many colors and patterns. With this being rather new to the field, not many eggs have been tested plus there is likely some error and bias. Even so, there are remarkable results. Some eggs were simple, just white. Some were speckled. Many were dull earthy colors, while others were green and blue. Given their close relationship, it is logical to assume dinosaur eggs could show any variations of what we see from either crocs or birds. Modern crocodiles have white eggs whereas modern bird eggs range in color and pattern. Interestingly, even within the same bird species there is a range in color, so it is entirely possible dinosaur eggs from the same species also vary in color. Three modern chicken eggs showing variation in colors and size. From Wikimedia Commons What is working with eggs like? Fieldwork: The basic process of removing eggs from the ground is very similar to that of removing fossilized bones. The approximate size of an egg is figured out and then the area around it is trenched until a plateau is formed. Next, a plaster jacket is made encasing the plateau. The bottom of this is removed until the whole thing can be “popped.” After which it is flipped and then is ready to be brought back to the museum. An egg at a new nesting site just after I uncovered it. Pic from the Two Medicine Dinosaur Center Jacketing an egg at Egg Mountain in Montana. Pics by D. O’Farrell. To find small fragments of eggshell and embryonic bones, removed rock is often sifted. Since they are so small—and also a rock surrounded by rocks—many times until sifted, the tiny bones or eggshell are not visible. Sifting for eggshell, here I am showing Paleontologist Barbie an example eggshell fragment. Pic from Coffeewithhallelujah After viewing the example fragment, my esteemed colleague Paleontologist Barbie was able to find an eggshell fragment. Can you find the piece of eggshell below? Pic from Coffeewithhallelujah Preparing and reconstructing an egg: Eggs tend to be more tedious and require more patience than normal prep work. Eggs are not that difficult to prepare, however, to an even greater extent than bones, they are very unforgiving. Reassembling a fossil bone after a mistake is not necessarily easy, however it is normally possible. The same often cannot be said for fossilized eggs. If you ever want to try and reconstruct a dino egg, just save the last chicken egg after cracking it and then try to reassemble. Remember, chickens are dinosaurs and their eggs make a decent modern analog to a classic theropod egg. Eggs in context- The Two Medicine Formation: To bring us all the way back to the beginning, what is the importance of studying eggs? Why bother? The primary geologic formation I have spent the last seven years working in is the Two Medicine and in terms of eggs, it is the most significant location in North America. One newly discovered nest I am fortunate enough to have an ongoing role in excavating and scientifically describing. From eggs and embryonic remains, the ecosystem of the Two Medicine is relatively well known compared to nearly every other formation. In terms of paleoecology, nesting sites show where adults felt safe and secure with enough food, water, and other resources. Within this formation was true evidence for parental care, particularly care in the form of nurture similar to birds. Behavior is nearly impossible to deduce from the limited fossil record, yet the care for young is strongly supported thanks to discoveries in the Two Med. Three dinosaurs from the formation have been linked to their eggs, Hypacrosaurus, Maiasaura, and Troodon. It may not seem impressive but three dinosaurs with embryonic remains is a truly remarkable find and incredibly rare. Even now, after over forty years of study, the Two Med continues to surprise with new nesting sites. Read about how the Two Medicine and Maiasaura was discovered: Additional information: http://www.ucmp.berkeley.edu/science/eggshell/eggshell_case1.php https://www.nps.gov/articles/mesozoic-egg-mountain-dawson-2014.htm https://serc.carleton.edu/research_education/mt_geoheritage/sites/augusta_choteau/paleontology.html http://www.georgialifetraces.com/2014/07/15/tracing-the-two-medicine/ http://www.georgialifetraces.com/2014/08/04/fossil-visions-in-the-two-medicine/ Hear me talk about my research on eggs and Troodon: Dinosaurs as living animals: Eggs allow us to see these animals as just that, animals. There is a reason many feel sad when seeing a baby dinosaur still in its egg, yet the same sadness tends to not be shown for adults. Why? The poor baby was deprived of an actual life and it is easy to relate. When covering a natural disaster, one goal of reporting is to humanize the story. In a similar way, when reporting on dinosaurs, it is important to try and do the same. Eggs allow us to come far closer to dinosaurs as true animals than I feel we ever will through bones alone. Eggs and reproduction give a window into the lives of these wonderful animals. When trying to describe what separates something living from an inanimate object, the ability to reproduce is used as a major criterion, therefore making it one of the most important aspects of dinosaurs to study in detail. Some Relevant Terms: These typically are used for modern birds and the classic theropods. Altricial: A developmental classification where at hatching, the offspring are relatively immobile, lack feathers or down, have closed eyes and are completely dependent on their parents for survival. Altricial birds include herons, hawks, woodpeckers, owls, and most passerine songbirds. Brood (n): The offspring of an animal which are hatched or cared for at one time. Brood (v): To sit on and keep warm. Brooding: To sit on and keep offspring warm when they cannot maintain their own body temperatures. Brood reduction: A reproductive strategy where the female lays more eggs than can be cared for and raised. The smallest and weakest of the brood typically starve or are killed by siblings. Clutch: Total number of eggs laid by a female in one nest attempt, often 3 or more. Conspecific: Of the same species. Cooperative breeding: Breeding system where non-parental adults assist other breeding pairs (usually their own parents) to rear offspring, instead of dispersing from the nest or breeding themselves. Incubation: The process by which parents keep eggs at the proper temperature to ensure normal embryonic development until hatching. In most cases, birds sit on eggs and transfer their body heat through a patch of skin known as the brood patch. In many species, only the female incubates; in other species, both males and females incubate. Less common is where only the male incubates. Precocial: Offspring are capable of a high degree of independent activity immediately after hatching. Precocial young typically can move about, have their eyes open and will be covered in down at hatching. They are generally able to walk away from the nest as soon as they have dried off. Siblicide: The death of a young animal usually as a result of fighting with siblings over food, common in years when food is in short supply. Further reading and information: https://www.amnh.org/our-research/paleontology/about-the-division/more/fossil-identification/dinosaur-eggs-fossil-identification http://www.ucmp.berkeley.edu/science/eggshell/index.php http://www.ucmp.berkeley.edu/science/eggshell/eggshell_hirsch.php http://www.ucmp.berkeley.edu/science/eggshell/eggshell5.php https://feederwatch.org/blog/raptors-make-good-neighbors-hummingbirds/ Images: University of California Museum of Paleontology: http://www.ucmp.berkeley.edu/ Yang et al. 2018: https://doi.org/10.7717/peerj.5144 Montana State University: http://www.montana.edu/ Two Medicine Dinosaur Center: http://www.tmdinosaurcenter.org/ Royal Tyrrell Museum: http://tyrrellmuseum.com/ Museum of the Rockies: https://museumoftherockies.org/ The Zuhl Museum: https://zuhlmuseum.nmsu.edu/ Dr. Tony Martin: http://www.georgialifetraces.com/ Mueller-Towe et al. 2002: https://www.researchgate.net/publication/260391508_Hatching_and_infilling_of_dinosaur_eggs_as_revealed_by_computed_tomography University of Calgary Hadrosaur eggshell: https://www.ucalgary.ca/drg/imagesort/00S000500 Oviraptor eggshell: https://www.ucalgary.ca/drg/imagesort/00S001300 Varricchio et al. 1997: https://www.researchgate.net/publication/232793785_Nest_and_egg_clutches_of_the_dinosaur_Troodon_formosus_and_the_evolution_of_avian_reproductive_traits Coffeewithhallelujah: http://coffeewithhallelujah.blogspot.com/2015/07/paleontologist-barbie-at-two-medicine.html Wikimedia Commons Citipati: https://en.wikipedia.org/wiki/Citipati Chicken eggs: https://en.wikipedia.org/wiki/Egg_as_food List of open access egg related papers: Thanks to the late Joe Gallo for this wonderful list. Disclaimer: For legal purposes, it should be noted links to an institution does not constitute endorsement by the respective institution and pictures are used here for educational purposes only. All rights belong to their respective owners. From the 2018 SVP meeting, my poster, which was a presentation on new dinosaur eggs. Pic from the Two Medicine Dinosaur Center Many thanks to J. Cozart and L. Murphy for writing some sections as well as edits. Thanks to D. Lawver, Ph.D. for reviewing the information presented. I especially would like to thank @Fossildude19 for assisting me and additionally thank these members for input and suggestions: @Troodon . @Seguidora-de-Isis . @HamptonsDoc . @-Andy- Eric P.

If you think you have found an egg fossil, chances are that it isn't actually an egg fossil. 98% of most found "eggs" posted here are not actual egg fossils. It could be a concretion or nodule. However, if you really want to learn about fossil eggs, here are a few links to get you started. Our resident Egg Studying Paleontologist, CBChiefski, has been kind enough to produce some in depth guides on egg identification. Think you found an egg? Read this first! Dinosaur Egg Guide- Basic Dinosaur Egg Guide - Advanced

Here is The Association of Applied Paleontological Sciences online guide for fossil dealers and other paleo related info for the 2019 Tucson (Arizona) fossil, gem and mineral shows. The guide lists dealers by speciality and venue. The guide has some blank pages (advertisements missing?). https://aaps.net/pdf/2019-AAPS-Guide-final-lo-res.pdf