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My partner and I visited Douglas Pass, Colorado last August: Eocene, Green River Formation, Parachute Member. The site represents a very shallow lake bed and is known primarily for fossil plants and insects. Recently I unwrapped her finds. The first one I think is some type of fossil seed. It is about a half inch long. The second, I think is a partial insect larvae, about an 8th of an inch. Let me know what you think. Thanks.

I collected this at Douglas Pass last year. Can anyone identify it? I was thinking it was Lygodium, but seeing other images of Lygodium I am now not at all sure and am thinking maybe Sapindus? Obviously I am not great on the plant IDs I am not hiving great luck in finding a good paper to identify flora from this site. I was really hoping for something like the Daniel Axlerod papers which are very comprehensive. I do have one called "Fossils from the Green River Formation" by Dayvault and another called " Common Plant Fossils from the Green River Formation at Douglas Pass, Colorado and Bonanza, Utah" by Johnson & Plumb. Both good, but short. "The Lost World of Fossil Lake" is also a good book that has helped me some. Anyone have any other good suggestions?

Hi everyone! I found this claw while anthill hunting on the White River formation of northeastern Colorado. It's about 6 mm in length and 4 mm tall. Honestly I'm not certain that it's a fossil, but if it is I'm really excited to have found it. My first guess is that it's a small bird, but it could very well be mammalian or reptilian. Any input is appreciated.

Found in northeast Colorado next to WY border. This looks like petrified wood but I have been fooled before.

I found these two neat little fossils in La Junta, Colorado. I'm not sure what they are but I have two guesses what they might be: barnacles or fish scales. I think it's from the Morrison formation but I'm not 100% sure! Any help would be appreciated

My family calls this a petrified egg, but a researcher called it fossilized (well, it is all speculative on what the heck it is). What would be the difference, or is that the same thing, fossilized and petrified? I googled it and it said there wasn't a distinction. Also looking for any info on what you think this egg might be, and wanted to share it with the community too. When I was growing up, once a year my mom would get out this petrified egg, and my brothers and I were allowed to hold it. It was always a very special treat! We would wrap a magazine around it, hold it up to the light, and we could see through it a little bit. My grandfather found it while digging a well on his ranch in Colorado. I had my mom and Uncle Keith write a note about the egg a few years ago. Uncle Keith use to carry it around with him when he was a kid. He even took his nail and dug a small hole in the crust. It's about 3" long, (bigger than a chicken egg), and has a hard rough crust. I have included an email from the Denver Museum, and from the University of Riverside, California about the egg. I feel very blessed to be its keeper. Thank you in advance, Kathy

If this is stone, it's very strange. Found in NE colorado near the WY border.

I was given the fossil fish below. It didn't come with any details, but this looks like a Green River Formation fish, which means it could be from Colorado, Wyoming, or Utah, right? Any thoughts on genus and possibly species? Thanks!

I was guessing some sort of accreation but when a friend dropped it I became confused. Any help greatly appreciated. Found on friends property in the foothills of Denver, CO. USA near the Fossil Trace GG (yes they actually have fossils imbedded in cliffs and other features on the golf course.) P.S. I ordered a centimeter graph pad and hopefully this will be last "improper" post

So I had a great week out there. Visited all the museums around as well as Dinosaur Ridge and Red Rocks. Also checked out Florissant fossil quarry and Pikes Peak. I have way too many photos to share all of them. I want to say for anyone out that way, go check out the museums. OMG they are amazing. It's hard to pick the best but one that stands out on top (because of more than just their fossil displays) is the Denver Museum of Nature and Science. Their wildlife displays are better than any zoo I've been to. Hands down simply an amazing place. The others are fantastic too. The Morrison Natural History Museum, Rocky Mountain Dinosaur Resource Center, Dinosaur Ridge (Discovery Center is between Red Rocks and Dinosaur Ridge), Florissant Fossil Quarry (and take a bag or two home also). If you take some bags home use more than one thin razor blade and a jewelers hammer. Don't stack the blades on top of one another but put them on the same plane side by side if need be. This will help you split the shale on thinner and more complete layers. Bits of wood found in the shale is still there and can be destroyed fairly easily I recommend a stabilizer for all the fossils found there. Despite not being able to collect like I do here in Missouri those living near the area that can visit these places often are very lucky. On a side note today I got to get out and collect some Pennsylvanian plants (wood) that I've never been able to collect before. There were some nice pieces too big to bring home sadly.

Hi everyone! I recently found a trace fossil near my house. I live in Southeast Colorado Springs and there's a lot of marine fossils near where I live. I found what I believe is an ammonite trace fossil. I'm having some trouble identifying it though. I'm not exactly sure what ammonite it's from as well as what formation it's from and what type of stone it's in. I brought it in to the museum I volunteer at and it was determined by the curator that it is not sandstone and it's most likely from the Late Cretaceous. I think it might be from a Hoploscaphites cheyennensis in silt-stone from maybe the Pierre Shale formation(?) but I don't know! The rock is slightly porous, if that helps. Help would be appreciated! Thanks!

I found this just N of Cass Colorado next to I-25 yesterday. I have checked online and can't find anything like it. Animal or vegetable. It is solid stone.

Hi Everyone. I was fortunate to be able to take a weeklong vacation trip the week of Labor Day, my fourth since I began collecting fossils. I wanted to visit friends and family and do some collecting. I was able to do all of that. It was busy, but there was also some quality relaxation time. It proved to be a good break. I flew into the Denver airport, rented a car and drove to Colorado Springs where I was invited to stay with my second cousin and her family. Next morning I was on my way to Florissant Fossil Quarry. I've known about Florissant for over 50 years and over 40 years ago I visited the National Monument, back when I was interested in fossils, but not into collecting them. This time I was intent on collecting and spent four hours splitting shale at the pay to collect quarry. The famous Florissant site was a lake during the late Eocene age. A number of eruptions from a nearby volcano buried animals and plants in beds of shale that were in turn covered by volcanic ash which beautifully preserved their exquisite details. These photographs show the exposure that's quarried, the area where guests like me can split the shale, and my finds from four hours of splitting.

Just as it says in the title, are these feathers from the Eocene Florissant Formation of Colorado. Or are they plant parts. They both are about 9mm long, 1/3 of an inch. Thanks for your help.

The holotype is a fantastic specimen, which is illustrated. Paleontologists Find Frog-Legged Beetle Fossil in Colorado Sci News, Aug 10, 2021 The paper is: Frank-Thorsten Krell & Francesco Vitali. Attenborough’s beauty: exceptional pattern preservation in a frog-legged leaf beetle from the Eocene Green River Formation, Colorado (Coleoptera, Chrysomelidae, Sagrinae). Papers in Palaeontology, published online August 5, 2021; doi: 10.1002/spp2.1398 Yours, Paul H.

Hey guys, My family and I are staying in Rocky Mountain national park northwest of Denver. Anyone know where you can find fossils near there?

I found this piece of late Cretaceous petrified wood in the Dawson formation of Colorado. Most of the piece however is this grey ash colored rock and I was just wondering, 1. What type of rock is it? I’m willing to do tests such as scratch and hardness if it will help. 2. How was it formed? 3. When was it formed? Did it form during fossilization or much more recently? Thanks for any and all help.

So my wife has a business trip coming up in Sept. I'm going with her and want stuff to do on the few days she's at the office there. End of the week we are hitting up some museum places around Morrison. I'm also thinking of hitting up the Florissant Fossil Quarry, because that's at least one place I can go and find something myself. I mean I'm certainly going to buy a few fossils on the trip because well why not. So there are a few things I'll visit without her just because I don't mind the hikes. I'd kind of like to find a few things myself and I know absolutely nothing about the area. I really don't want to get to far away from those areas because I am in a rental, have to pick her up from work, and again I don't know the area. I'll not be taking a lot of equipment because of other stuff and room in the car. I'll have hammer and chisel basically and a pack to carry stuff in. Thanks for any help. Robert

In Colorado there is a formation called the Dawson Formation also known as the Dawson Arkose Formation. The most common fossil by far is petrified wood and although I haven’t found any vertebrate fossils from dinosaurs and mammals have been found. It covers a relatively large time span from late Cretaceous to early Eocene, about 70-54 million years old. A member that has also found fossils in this formation, Blake @FossilDudeCO. Although it has been over three years since he was on his posts have still helped. He said that further south is Eocene but higher north in Parker and Aurora is Cretaceous and from the cinnamon tree family. That’s all the basic info, now it’s time for the pictures. The next four are wet to show the color a bit better. The next three are polished via rock tumbler. The next image sparkles like sunlight on snow but you can’t really tell with a picture. While most are brown and black there are hints of color everywhere. Red, and clearly wet. Orange Yellow is mixed in a lot of them with a lot of it being a yellow brown or yellow white color. This is the only rock I have found with green in it. Very strange if anyone knows what any of these minerals are I would love to know. Blueish Purple grey Ill take pictures of more purple ones shortly. Here are just more pictures, Enjoy The largest piece, the first image, is my favorite and largest find being 8.1 pounds (3.7 kilograms). FossilDudeCO said in a topic, "It is thought that the trees fell into standing water and began to deteriorate that is why we don't see lovely rings or any more definition to the wood, rather just strange mashed up chunks and bright colors!" Which I am perfectly fine with. In case you didn't read between the pictures, if anyone knows what any of these minerals are I would love to know.

I found this today on private land while hunting for calcite SE of Denver Colorado. It was in a gulch mostly buried by sand that is very quartz heavy. Please help with ID! It is very heavy!!!

I found this last year at the Sunnyside mine, Eureka mining district, San Juan county Colorado. My initial thought was this is Lapis, however I have seen specimens of lapis that do not look quite like this. Thank you for any input.

I just got back from an amazing and very fruitful week of fossil collecting on the White River Formation in northeastern Colorado. The White River Formation is a very easy and fun rock unit to collect vertebrate fossils on. The White River Formation was deposited during the very latest Eocene and the early Oligocene, though the faunal diversity in the areas I was collecting on suggest it was laid down during the Orellan North American Land Mammal Age, which centers on around 33 million years ago during the Rupelian age of the Oligocene Epoch. I am very lucky to have a grand uncle Gary (no biological relationship to me, is a close family friend who we’ve called “uncle” since I was a toddler) who is a cattle rancher up in northeastern Colorado, and he happens to have a pretty good amount of White River exposure on his property, in addition to some of the neighboring ranches of which Gary knows the owners and helped me to secure permission to collect on a few of them. He really is a great guy and is a real life true American cowboy. He has an interest in natural history and was eager to hear all about the fossils and geology of the area, though has never had the formal education or done the research to learn much about what’s out there. This is the second fossil collecting trip I’ve made to the ranch, though the first one where I’ve stayed for more than one night. The place truly is an amazing trove of fossil treasures and I can’t wait to tell you all about my week! In this thread I’ll make one post for each day (so as to not hit the picture limit too soon). Once I have the fossils prepped I’ll give updates here as well. Day 1, Sunday: My first day at the ranch began, ironically, at my own house. I had packed up the Jeep the night before with my field bag, two coolers filled with seven day’s worth of food, a suitcase full of clothes, and other such supplies for my fossil safari. I left my home early in the morning, took I-76 east to Fort Morgan, and then headed north to the ranch, in total about a 2.5 hour drive. The rest of the morning and early afternoon I spent visiting with and going over logistics with Gary and his wife and settling in at the ranch house I would be staying at, a property that used to be the home of another rancher before Gary acquired the property in 2002. They still maintain the house and it has both electricity and running water, so it makes a fantastic guest house and a place to stay when they’re doing work over on that side of their land. In the evening after I had made myself a quick dinner I decided I wanted to head down to a very productive exposure I had collected on last September for the evening. There was a partial oreodont skeleton that I had discovered eroding out of the hill the last time I was up there, and I wanted to see if there were any more bones there that had eroded out and I could collect. I picked up a few more bones from the feet and ankles that had been exposed in the last eight months and decided to take a scenic route back to my vehicle. A photo of the area of exposure I was in Sunday evening. This piece of badland will become very important throughout the rest of the week... On my walk back I walked over a ridge that I had apparently never been over, becase on a flat wash I noticed a pile of bone fragments. I approached the pile assuming that it would be yet another exploded tortoise shell that are so common in the area. As I got closer however, I was delightfully surprised to see the distinctive black color of fossil enamel, and a bit of digging revealed an eroded Subhyracodon jaw section, along with several loose teeth that I presume had come from the same section of jaw. This find, along with an oreodont jaw section I found later on while walking back to the Jeep that night, would be but a foreshadow of the big finds I would make later in the week. Two photos of the Subhyracodon jaw section as it was found in the field. The jaw section and some teeth after I had cleaned them up a little bit at home this afternoon.

Well with the last year of moving and renting and moving again, I haven't had much time to do much of anything on the fossil front. The Pictured Cliff Sandstone formation, Late Cretaceous near Durango, Colorodo. Spotted these large rock faces with ripple marks and decided to be a geology nerd and scramble as far up the slope as possible to snap a few photos. These ripples were likely deposited at the edges of the Interior Seaway, Late Cretaceous. In 10m of water. At least, that's what the paper suggests. (Depositional Environments of The Pictured Cliffs Sandstone, Late Cretaceous, Near Durango, CO.) This was as close as I dared in loafers, on a decent slope, along a busy highway. haha I did find what looks to be an ichno fossil nearby (the paper suggests Thalassinoides and Opbiomorpha ). The Fruitland Formation sits on top of the Pictured Cliffs so it could have come from either I suppose. More exciting finds are around the corner, I wait patiently. Cheers, Brett

I've always wanted to visit the Florissant Fossil Quarry due to my interest in paleoentomology but for one reason or other, I was never able to make it out there. I was finally able to make a detour out during a roadtrip returning from a funeral last week. There were beautiful calm skies, which was lucky too since heavy rains were forecasted for the next 2 days. After a good 5 hours, this is what I had to show for my efforts: Most pieces will have unidentifiable organic smudges. Aside from that, small leaves are the most common readily recognizable fossils. I am a terrible botanist, if anyone has any IDs, that would be awesome.