ewolff Posted February 9, 2014 Share Posted February 9, 2014 Can anyone ID this fossil by chance? I found it near the town of Llano, TX. It has several concentric rings, but no apparent radial lines. I'm admittedly a bit of a novice, so thank you in advance. Link to comment Share on other sites More sharing options...
Fossildude19 Posted February 9, 2014 Share Posted February 9, 2014 Looks like a concretion to me, rather than a fossil. This from the wiki link supplied above: "Depending on the environmental conditions present at the time of their formation, concretions can be created by either concentric or pervasive growth (Mozley, 1996; Raiswell and Fisher, 2000). In concentric growth, the concretion grows as successive layers of mineral accrete to its surface. This process results in the radius of the concretion growing with time." Regards, Tim - VETERAN SHALE SPLITTER VFOTM --- APRIL - 2015 __________________________________________________ "In every walk with nature one receives far more than he seeks." John Muir ~ ~ ~ ~ ><))))( *> About Me Link to comment Share on other sites More sharing options...
jgcox Posted February 9, 2014 Share Posted February 9, 2014 without a sharper in focus photo my best guess would be a split concretion also. Link to comment Share on other sites More sharing options...
Herb Posted February 9, 2014 Share Posted February 9, 2014 "Absence of evidence is not evidence of absence"_ Carl Sagen No trees were killed in this posting......however, many innocent electrons were diverted from where they originally intended to go. " I think, therefore I collect fossils." _ Me "When you have eliminated the impossible, whatever remains, however improbable, must be the truth."__S. Holmes "can't we all just get along?" Jack Nicholson from Mars Attacks Link to comment Share on other sites More sharing options...
ewolff Posted February 9, 2014 Author Share Posted February 9, 2014 Thank you all for the information! Apologies on the initial image quality; I've included another photo that I think is slightly better. It's roughly the size of a dime. Looks a bit different from most of the images I've seen of concretions, but again, I am a novice at identifying such things. So with the better image, would it still appear to be a concretion? Link to comment Share on other sites More sharing options...
ewolff Posted February 9, 2014 Author Share Posted February 9, 2014 Here is the other photo: Link to comment Share on other sites More sharing options...
Xiphactinus Posted February 9, 2014 Share Posted February 9, 2014 (edited) Probably concretion, but possibly the end of a fish vertebra? [edit - based on last photo...definitely a concretion.] Edited February 9, 2014 by Xiphactinus Link to comment Share on other sites More sharing options...
Ludwigia Posted February 9, 2014 Share Posted February 9, 2014 I agree with everyone to date. Here's a baryte concretion which I found in Oligocene layers to give you an idea. Greetings from the Lake of Constance. Roger http://www.steinkern.de/ Link to comment Share on other sites More sharing options...
ewolff Posted February 9, 2014 Author Share Posted February 9, 2014 (edited) Thank you so much for all the input. I appreciate the confirmation of it being a concretion. I suppose I'll have to work a bit more on being able to tell the difference, haha. To my untrained eye (and from a cursory search) it looked a bit like the base of some ferns from the Ediacaran Period. Thank you, again! I look forward to reading this board and learning more about the world of fossils! Edited February 9, 2014 by ewolff Link to comment Share on other sites More sharing options...
ewolff Posted February 9, 2014 Author Share Posted February 9, 2014 Btw, Ludwigia - I really appreciate the photo reference. I'm still a bit confused though because yours looks smooth and like its part of the rock. Mine has a definite surface, which rises up from the rock. Is this a common feature in concretions? Link to comment Share on other sites More sharing options...
Auspex Posted February 9, 2014 Share Posted February 9, 2014 Btw, Ludwigia - I really appreciate the photo reference. I'm still a bit confused though because yours looks smooth and like its part of the rock. Mine has a definite surface, which rises up from the rock. Is this a common feature in concretions? Yours has weathered some; the raised rings were harder/more resistant. "There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant “Try to learn something about everything and everything about something.” - Thomas Henry Huxley >Paleontology is an evolving science. >May your wonders never cease! Link to comment Share on other sites More sharing options...
ewolff Posted February 9, 2014 Author Share Posted February 9, 2014 Hmm, that's really interesting. The surface is different from the rest of the rock though..? It's like an additional layer that's stuck to it. Forgive all my inquiries, I'm just finding this really interesting and am enthusiastic to learn more. Link to comment Share on other sites More sharing options...
Auspex Posted February 10, 2014 Share Posted February 10, 2014 ...The surface is different from the rest of the rock though..?... This concretion never escaped from the matrix that gave it birth. "There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant “Try to learn something about everything and everything about something.” - Thomas Henry Huxley >Paleontology is an evolving science. >May your wonders never cease! Link to comment Share on other sites More sharing options...
ewolff Posted February 10, 2014 Author Share Posted February 10, 2014 Ok, that makes sense. Thank you so much! Just for personal reference in the future, how would I tell the difference between what I found and something like this (aside from the obvious plant imprint next to it): http://www.discussfossils.com/forum/uploads/1040/Primochandelabrum_Leicester_Museum1.jpg ? I realize I'm highly unlikely to encounter one, but just so I don't make the same mistake again. Link to comment Share on other sites More sharing options...
Fossildude19 Posted February 10, 2014 Share Posted February 10, 2014 (edited) I've made some circles on your pic, that illustrate the harder layers of the concretion, that were a bit more resistant to wear than the inner, softer (relatively) layers. Concretions, at least the ones that are concentrically built, add layer after layer of sediment, and sometimes different minerals form and in some layers and not in others. So the raised portions of your circles are the harder layers. And, as Auspex mentioned, the concretion is still within the hardened sediments that it originated in. Hope this helps. Regards, EDIT: to answer your question, the picture you posted, you can see the matrix (rock) is all the same - no difference in the rings, whereas your's has definite layers. Edited February 10, 2014 by Fossildude19 Tim - VETERAN SHALE SPLITTER VFOTM --- APRIL - 2015 __________________________________________________ "In every walk with nature one receives far more than he seeks." John Muir ~ ~ ~ ~ ><))))( *> About Me Link to comment Share on other sites More sharing options...
ewolff Posted February 10, 2014 Author Share Posted February 10, 2014 Wow! Thank you Fossildude!! I believe you have put all my questions to rest. I thought it might be something along those lines, but not having the background and having found it in the Llano uplift, I still was just wondering a little. Thank you for taking the time to lay things out for me. You have definitely gone above and beyond. Link to comment Share on other sites More sharing options...
Fossildude19 Posted February 10, 2014 Share Posted February 10, 2014 You're more than welcome. Regards, Tim - VETERAN SHALE SPLITTER VFOTM --- APRIL - 2015 __________________________________________________ "In every walk with nature one receives far more than he seeks." John Muir ~ ~ ~ ~ ><))))( *> About Me Link to comment Share on other sites More sharing options...
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