eldr62 Posted February 8, 2018 Share Posted February 8, 2018 https://imgur.com/a/J0Twa Originally posted on r/fossilid on reddit.com. Did not get much reception. I literally know nothing about fossils except a few tidbits in recognizing basic things like crinoids. I do not remember exactly where it was found, but geologic maps indicate my area, Columbia, Missouri, is roughly in the carboniferous layer. I'm sorry I don't have many good views of it--I do not have any good tools to readily chip away at it. Let me know if you guys have any more questions! Thank you so much! Link to comment Share on other sites More sharing options...
izak_ Posted February 8, 2018 Share Posted February 8, 2018 Crinoid or blastoid calyx? How big is it? Btw here it is (for the people who don't want to look in that link?) 1 Link to comment Share on other sites More sharing options...
D.N.FossilmanLithuania Posted February 8, 2018 Share Posted February 8, 2018 If it is from Carboniferous, the determination is Trigonocarpid seed fern. 1 Link to comment Share on other sites More sharing options...
supertramp Posted February 8, 2018 Share Posted February 8, 2018 maybe a leucite crystal in a volcanic rock ciao Link to comment Share on other sites More sharing options...
Ludwigia Posted February 8, 2018 Share Posted February 8, 2018 1 hour ago, supertramp said: maybe a leucite crystal in a volcanic rock ciao Agreed. Or Analcime. Greetings from the Lake of Constance. Roger http://www.steinkern.de/ Link to comment Share on other sites More sharing options...
Rockwood Posted February 8, 2018 Share Posted February 8, 2018 Could we have a closer look or larger file ? Those look like they could be crinoid bits to me. I suspect this may be volcanic ash, which can be very fossiliferous. Link to comment Share on other sites More sharing options...
izak_ Posted February 8, 2018 Share Posted February 8, 2018 34 minutes ago, Rockwood said: Could we have a closer look or larger file ? Those look like they could be crinoid bits to me. I suspect this may be volcanic ash, which can be very fossiliferous. I agree Link to comment Share on other sites More sharing options...
DPS Ammonite Posted February 8, 2018 Share Posted February 8, 2018 It is not a crystal in a volcanic rock. It is most likely an interior mold of a crinoid calyx surrounded by an empty space where the calcite calyx has dissolved away. Note numerous exterior molds of crinoid stems in a rock that is most likely a chert found in a limestone. Compare this rock to the similar cherts with molds found in the Mississippian Redwall Limestone from Northern Arizona. 4 My goal is to leave no stone or fossil unturned. See my Arizona Paleontology Guide link The best single resource for Arizona paleontology anywhere. Link to comment Share on other sites More sharing options...
eldr62 Posted February 8, 2018 Author Share Posted February 8, 2018 2 hours ago, DPS Ammonite said: It is not a crystal in a volcanic rock. It is most likely an interior mold of a crinoid calyx surrounded by an empty space where the calcite calyx has dissolved away. Note numerous exterior molds of crinoid stems in a rock that is most likely a chert found in a limestone. Compare this rock to the similar cherts with molds found in the Mississippian Redwall Limestone from Northern Arizona. I think this theory makes sense! I didn't realize those calices could get so large. Link to comment Share on other sites More sharing options...
eldr62 Posted February 8, 2018 Author Share Posted February 8, 2018 3 hours ago, Rockwood said: Could we have a closer look or larger file ? Those look like they could be crinoid bits to me. I suspect this may be volcanic ash, which can be very fossiliferous. I will try to take more pictures today! I tried to get a look underneath the rock lip, but my simple phone camera did not do it justice. I will also get some close-ups of the opposite side with all the crinoid imprints. Thank you, everyone, for all of your ideas and thoughts! I really appreciate it! This has already been a conversation piece and I would like to at least have some theories as to what it is. The geometric shape really throws me for a loop! Link to comment Share on other sites More sharing options...
Xiphactinus Posted February 8, 2018 Share Posted February 8, 2018 Absolutely 100% an internal mold (steinkern) of a crinoid calyx. Given the locale, that is most likely the chert that lies within the Mississippian Burlington Fm. It's chock full of crinoid/blastoids like that. 2 Link to comment Share on other sites More sharing options...
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