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I was wondering what this was? I believe it may be a concretion but I am unsure, and may be misidentifying it.

I made a trip to bison creek yesterday. Not it’s real name, but where I found the bison. So it seems an apt name. I packed my backpack and hip waders in my trunk and headed out. I got a half mile down the road and realized I’d forgotten to bring a change of pants. I told myself “I’m running late. I’ve got my hip waders to cover my pants. I’ll be fine. I only had 2.5 hours to explore, splash around the creek and play with any new fossils or rocks I might find of interest. I needed to leave by 3:00 so I could go to a send off party for a friend who is going to go minister to the Lakota tribe in South Dakota for 2 years and hopefully establish a thriving Celebrate Recovery group there. Anyway, as I was putting on my waders I could see sunlight passing through in a few places. I guess they weren’t made for kneeling and digging and excavating fossils. I got my gear and headed down to the creek. It was bright and sunny and in the low 50s. Great weather for hunting. I stopped by the bison dig on my way downstream. The last cavity I had dug the articulated leg out of had collapsed in on itself. We had rain one day last week so I’m sure that helped it along. I thought I’d dig through some of the old collapsed dirt where I’d found bones before. I found one more vert. Hard to tell, but there is bone there. I moved on down the creek. There aren’t many obvious fossils in the creek, but there are lots of cool rocks, concretions and minerals. If you know me I’m fascinated with concretion. Here is a view of the creek. Notice the layers on the right. The gray extends 3-4 feet up into the bank. Then the Pleistocene layer begins. There is s small tan layer. I think the Pleistocene begins above that. Here is a cool looking septarian concretion. I call these turtle rocks. They’re aren’t turtles, but that’s what they reminded me of. It has strong mineral veins of brown, most likely aragonite running through it. The other side. I like the richness of color. It’s probably just iron stain, but I like it. Most septarians around these parts are a dull gray. I walked a little further and came to this part of the creek with a high bank. This area seems to be a geological irregularity of some kind. This may be one of those instances where it lies in unconformity or something like that. I know for sure the dark gray is Eagle Ford Group, Arcadia Park Formation I believe. The light layer above it up to the next gray layer is either Austin Chalk or Eagle Ford. It could be a layer of Austin Chalk, which becomes more dominant to the east. The Austin Chalk overlays the Eagle Ford. Then above the tan a thin layer of gray where it is Pleistocene. The tan layer thins out to the right and disappears altogether a few feet to the right of the pic. There is a big chunk of light gray shale that had fallen from the bank. Concretions are scattered along inside the bank. Some quite large, very cool and pretty. There are frequent avalanches and here you see evidence of that on the left. There is a concretion in the creek probably from the avalanche. I think I’d be just as happy sitting curiously breaking open the concretions and studying them. They’re just fascinating! Of course then I’d want to take them all home. The creek bed is a slippery shale. I think this is so cool looking! The cavities are filled with a druzy type calcite with some aragonite too. I’m not use to seeing small little ones like that. The ones I find near Dallas are huge and not druzy. The size of these overall though are huge. Here is s close up of part of it. I didn’t attempt to take any of it. I couldn’t carry it, but it sure is pretty. Also, this is s high avalanche risk area. It concerns me more than the NSR in terms ov avalanche risk. In this area there are lots of minerals oozing out in places. It colors in the shale. I have been told there is fish fossil material in this creek. I haven’t found the exposure yet though. This piece on the bottom right looked fishy to me. There are other parts that looked like it had scales and also the pattern of fish scales was scattered across the piece at the top center. I’m not sure what it is. It is in fine delicate shale though. There was this white gelatinous substance that looked to be oozing out of the rocks in places. Very weird looking. I don’t recall seeing such a thing before. The bank is streaked with minerals that have been in solution and flowed down. Some looks like sulfur yellow. Some orange and white. There are also fine calcite and possibly gypsum crystals in the layers. Some like fine needles. They may be some other mineral too. Anyone know what the white stuff is? It was oozing out of a long vein across the creek. There was another area where the rock and water were stained orange from what looked like iron leaching out. This septarian is over 5 feet long. I moved on down the creek. There was a large gravel bar just down the creek filled with septarian nodules both whole and fragments. This one isn’t too pretty, but I think it has potential. Maybe a weak acid wash would brighten it up. It looked predominantly aragonite. You don’t see many like that this big. I kept moving. On my left was a sand bar where the Pleistocene layer was at the surface. I spotted an odd looking thing that looked a bit like an exposed root. I went to check it out. Woohoo! A bone or a fragment of one. I put down my pack and pulled out my chisel to remove the dirt around it. Bones can be fragile. I could just pull it out, but I risk breaking and losing some of it. So I always dig around bones or fossils to free them up before pulling them out. It kind of looks like the distal end of a humerus, but I’m not sure from what. The epicondyles are broken off the other side and it’s pretty worn. Ill post more later. I’m not half done yet.

The open access paper is: Clements, T., Purnell, M. and Gabbott, S., 2018. The Mazon Creek Lagerstätte: a diverse late Paleozoic ecosystem entombed within siderite concretions. Journal of the Geological Society. Journal of the Geological Society (2018) 176 (1): 1-11. https://doi.org/10.1144/jgs2018-088 https://pubs.geoscienceworld.org/sepm/jgs/article/545488/the-mazon-creek-lagerstatte-a-diverse-late https://pubs.geoscienceworld.org/jgs/issue/current Another open access paper is: Briggs, D.E., Liu, H.P., McKay, R.M. and Witzke, B.J., 2018. The Winneshiek biota: exceptionally well-preserved fossils in a Middle Ordovician impact crater. Journal of the Geological Society, 175(6), pp.865-874. https://pubs.geoscienceworld.org/jgs/article/175/6/865/548502/the-winneshiek-biota-exceptionally-well-preserved https://pubs.geoscienceworld.org/jgs/issue/175/6 Yours, Paul H.

Ok, when I wake up, drowzy, make some coffee, then into the computer room. This is what I see. Lots more in the display cases behind me with no room left! Then I open the top drawer, more crab fossils, forgot about those. Lots more in the garage! then I realize, there are two more in the glove boxes of my 2 trucks. Now I wonder where else I have more? We all have problems. We all need help. but for me, Im not sure how I can find a cure? But for now, I will just smile and go on. This is a problem I can live with. All I need now is more to prep. Do I have a disease? RB

ok not quite sure what these are find one every now and then...they have an odd coating dropped a couple in the acid bath for a few minutes and looked at them through a microscopic camera and found all sorts of little goodies... so wondering could these be some type of poo??.....fossilized feces. Coprolites...??. ..fish? turtle? lizard?...??

A short but informative article about concretions up to 4 meters in diameter. Also a photo gallery of the area they are found in. http://www.geologypage.com/2016/10/valley-of-balls.html

Hello all, My friend gave me some odd shaped concretions, and I was wondering if anyone has experience preping any like these?

I bought two crab concretions from a guy about 3 weeks ago. Not happy with these concs, but if you don't gamble you don't win. In this case, I lost. These will be b-grade crabs. Simply not good enough to make it into my crab collection. In the second picture you can see what I see when I sit back and just look at what ive done. In this case, Im sittin back and lookin at how im doing with the 'rock smoothing'. Lookin purty good for a b-grade piece of cow poop. Im also very spoiled. Belive me, with what I payed for these and the amount of time spent,,,, after I sell these dang things I will hopefully make about $10 an hour!!! Just letting you know that there is no moneys to be made on prepping fossil crabs. Oh, these are Pulalius vulgaris from the Lincoln Creek Formation in Washington and Eocene in age. RB

Found this in the city of Tbilisi, Georgia. It was discovered while digging a foundation, under 6 feet of ground. I also found a smaller version of the pictured one, only 1/2 this size. That one was found in kobuleti, Georgia. Also found aproximately 6 feet underground. Both have a prolate spheroid shape. Could not find any flat areas on the surface. Size: 14" ×16" Weight: 38.8 pounds.

Is this a flat concretion? I found one like this out on some property my son is building on. I thought it was an artifact because of the hole. The land is virgin and a known area where Native American had a village. There is a historical plaque by the land. It is in Virginia.

Exceptionally preserved fossils: critical evidence of the history of life, December 8, 2013 https://www.youtube.com/watch?v=V8WEdTbPNnM Derek E.G. Briggs Department of Geology and Geophysics Yale University, and Director, Yale Peabody Museum of Natural History One interesting comment that Dr. Briggs made towards the end was that the Herefordshire Lagerstätte is still unique for soft bodied animals in carbonate concretions in bentonite. He felt that there surely must be additional lagerstätte of this type is just nobody has systematically and specifically looked for them. This seems like a project where fossil hunters, who know of carbonate concretions in bentonite bed(s) could make a contribution to paleontology. A description of the Herefordshire Lagerstätte is at: The Exceptional Silurian Herefordshire Fossil Locality By Marc Srour, June 11, 2012 http://bioteaching.com/the-exceptional-silurian-herefordshire-fossil-locality/ and Siveter, D.J., 2008. The Silurian Herefordshire Konservat-Lagerstätte: a unique window on the evolution of life. Proc. Shropsh. Geol. Soc, 13, pp. 58-61. http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.542.3450&rep=rep1&type=pdf http://www.shropshiregeology.org.uk/sgspublications/Proceedings/2008 No_13 009 Siveter Lagerstatte.pdf A related online paper is: Parry, L.A., Smithwick, F., Nordén, K.K., Saitta, E.T., Lozano‐Fernandez, J., Tanner, A.R., Caron, J.B., Edgecombe, G.D., Briggs, D.E. and Vinther, J., 2018. Soft‐Bodied Fossils Are Not Simply Rotten Carcasses–Toward a Holistic Understanding of Exceptional Fossil Preservation. BioEssays, 40(1). https://www.researchgate.net/publication/321379006_Soft-Bodied_Fossils_Are_Not_Simply_Rotten_Carcasses_-_Toward_a_Holistic_Understanding_of_Exceptional_Fossil_Preservation_Exceptional_Fossil_Preservation_Is_Complex_and_Involves_the_Interplay_of_Numero https://www.researchgate.net/profile/Luke_Parry2 Yours, Paul H.

Found these recently and thought they were interesting.

Thought I'd share this strange concretion. Found 50 miles southeast of nipple mountain. Has anyone ever seen anything like it?

I think we have all seen the crabby beauties that @RJB and @Doctor Mud have revealed from their Stony Concretion prisons. Now I want to get in on that action, but I don't (currently) have a passport for a trip to NZ. Any sites in the US anyone knows of?

Any thoughts?

Im starting to run out of room in my crab display case so i put some on my desk. Quite nice for me. I do have two guys who want to buy a Tumido from me, but I have a really hard time letting these go. I seem to fall in love with them while prepping? And its really hard to get a really good Washington crab. I guess the collection will just keep on growing. I dont think i will have a problem with that. Life is good. RB

I have really been itching to go out and get some crab concretions from the Lincoln Creek formation. I am not l looking for any extreme high quality specimens I just want to be able to get my hands on some concretions, so if anyone has locations that put out quantity over quality (preferably public land) please reply below or pm me. Any help is greatly appreciated!

I was watching the Clint Eastwood movie “The Good, the Bad and the Ugly” recently and it made me think about collecting Mazon Creek concretions and how the movie title applies to them. Let’s start with a couple of the “Good” things: -Over the years there has been numerous books and articles written about the Mazon Creek area and concretions and they provide outstanding information for the collector of all levels. -With about 400 species of flora and about 320 species of fauna that are found in these ironstone concretions plus the remarkable preservation of so many soft bodied animals, I feel that it rivals the fossils found in the Burgess Shale and Solnhofen.

Hi everyone! I’m not a collector or even a hobbiest (yet!) but I came across this forum looking for a way to start learning and to help me ID some interesting things I found the other day. I was walking with my dog in Cranberry Township PA (20miles north of Pittsburgh) and noticed a number of darker, reddish, oddly shaped stones that stood out against the hillside of crumbled gray shale that had been pulled out (possibly from as far as 50 feet down or so) in digging a drainage pit for a new development. Most of what I saw just looked like concretions formed around river stones or something like that (some were split in half so they almost resembled clams) but in one area there were pieces that looked different, some with fairly conspicuous tooth or bonelike shapes. I rinsed mud off of them with warm water and started scrubbing a bit with a brush but I noticed that the lightest areas on a couple pieces are fairly soft (I can scrape them with my fingernail) so I thought I'd better stop until I figured out what was what. I don’t really know anything about this stuff yet, but I loved looking for ferns, etc and even found a trilobyte once as a kid and so I was kinda thrilled to have maybe found something interesting. Of course, they could just be a pile of neat rocks too, haha... So what do you think I have here? Just organic looking concretions or something cooler? Thanks! (note: I embedded the images instead of directly attaching them, so if you click on them you'll be able to see higher-resolution versions)

Hi, I'm new here. I'm a retired geochemist with an ongoing interest in fossils - I love the hunt, I love to imagine the amount of time elapsed between when the animal lay in the sediments and died and when I picked it up. Mind blowing. Would like to connect with others to learn and share. I have found some, what I think are concretions, in some debris from the Chinle and/or Moenkopi Formations in the Indian Creek area of Utah. I've been going there for 30 years and have never seen anything like it. I have found dinosaur bones in the area. What's the defining difference between dinosaur eggs and concretions? These are definitely not made of SS - probably silt? cracked surface (like mud cracks), gray, inside one has the "septarian" look, others just plain. Anybody else find these in the area?

I see these quite often embedded in limestone. I am just curious what this mineral is. Rusty in color and sometime in a molten shape rather than round.

Hello everyone, I recently purchased a lot of Mazon creek concretions for an extremely low amount of money. From this and the picture I assumed it meant most were just concretions, but I could see two ferns so I bid for it and easily one. I'm not familiar with Mazon creek flora and fauna, so I decide to ask all of you if they are just rocks or fossils, and if they are fossils, what type. There's sixteen so I'm going to post two a time (perhaps two a week depending on how fast they are identified) as to not overload all of you. First up is the two I know are fossils, both of which I think are ferns. Species or genus might not be possible to find out, but it's worth a try.

I've tentatively identified a number of Mazon pieces in my possession, and I was wondering if I could get some confirmations or corrections from those of you (all of you) who are more knowledgeable and experienced than I. The first (#1) based on length, fossilization curvature, and the pyritized mouth and throat slit, I believe to be Gilpichthys greenei.

Ok This wall had me looking at it for some time, do you see anything fossil related? location 2km north of amathus ancient city, limassol, island of cyprus and on the opposite hill :

Here it is, the tail end of winter and I find myself composing a "trip report" from way back in May!!!! Please excuse the tardiness, but it took 9 months for me to pick away at the concretions I collected and extract the fossils within. It was a learning process and I must admit, I DESTROYED the nicest ammonites that I had found. Instead of learning techniques on my lesser specimens, I jumped in and "prepped" the biggest and best first. What I ended up with were many bits and pieces of crumbled ammonites. And super glue did NOT fix the problem. The issue at hand: the matrix is very hard and the ammonite very delicate. Not a good combination for not knowing how and hastily prepping something. It was Memorial Day weekend, time for an extended road trip after a long winter. My wife and I had never been west of Minnesota in the 30 some years since departing Ohio for the Gopher State. So we thought the time was right to experience what our next door neighbor, South Dakota, had to offer. I must say, we were thoroughly impressed with the state's variety of landscapes and great people. Our excursion actually extended into a bit of Wyoming. From Devil's Tower, we worked back through the Black Hills/ Mount Rushmore/Black Hills Institute and the Badlands National Park, each with it's unique topography. I recommend visiting these sites to anyone that has not. Well worth the trip!!! As our vacation was drawing to a close, we again crossed the grassy plains (though we envisioned amber waves of grain, not grass) and overnighted in the town of Mobridge. The next morning, I was to meet up with Grady (gradycraft on the Fossil Forum) for a little fossil hunting in the Fox River Formation while my wife relaxes with her books at the motel. Though I was totally impressed with the state of South Dakota, I was not impressed with Mobridge's accommodations. Here is a view from our hotel room!!! Nothing to see but a large car wash out your window. Now I was going to leave my wife to this, while I was off enjoying myself. I did honestly feel guilty, but not guilty enough to stay behind! Grady met me in Timber Lake and from here, our adventure began. Shortly after exiting Timber Lake, the vastness of this landscape became apparent again. One could honestly feel what it was like for the indigenous Indians before European settlers arrived. One could envision herds of buffalo taking advantage of the lush grasslands around the area. A spectacular place!!! Here I am following Grady on the way to who knows where. Fifteen miles on gravel roads and we turn onto a "path" leading through a few rickety wire gates. Then off we were again. Still flat as a pancake, NO rocks in sight. Where are these fossils I kept asking myself. If it wasn't for the great scenery, I might have worried more that we were on some "wild goose chase". Another 10 miles off the beaten path and I was really beginning to wonder about Grady!!! Finally, a little variety in the landscape showed up and then we dropped into a small valley with a stream running through it. I was ecstatic when I saw Grady's brake lights. We must be there.