brus Posted November 17, 2016 Share Posted November 17, 2016 Hello,is this part of rudist or another shell? Link to comment Share on other sites More sharing options...
Ludwigia Posted November 17, 2016 Share Posted November 17, 2016 Once again, we ask for more detailed information. Location? Stratigraphy? It looks to me like it may be part of a coral. Greetings from the Lake of Constance. Roger http://www.steinkern.de/ Link to comment Share on other sites More sharing options...
ynot Posted November 17, 2016 Share Posted November 17, 2016 A scale and other angle of views would help too. Tony Darwin said: " Man sprang from monkeys." Will Rogers said: " Some of them didn't spring far enough." My Fossil collection - My Mineral collection My favorite thread on TFF. Link to comment Share on other sites More sharing options...
brus Posted November 17, 2016 Author Share Posted November 17, 2016 Yes,is big about 4cm and found in some mud in Croatia.. Link to comment Share on other sites More sharing options...
Plantguy Posted November 18, 2016 Share Posted November 18, 2016 I think that layering on the opposite side of your specimen cinches it for me but I'm not a rudist guy. I think Ive seen Mesozoic aged sediment references there as well. Wait for Roger, Tony, Tim, Abyssunder or the other ID regulars to chime in........ Cool critter/texture... Regards, Chris Link to comment Share on other sites More sharing options...
fifbrindacier Posted November 18, 2016 Share Posted November 18, 2016 16 hours ago, Ludwigia said: Once again, we ask for more detailed information. Location? Stratigraphy? It looks to me like it may be part of a coral. Coral, or maybe also fenestrate bryozoan. On the remnants of a Shell. "On ne voit bien que par le coeur, l'essentiel est invisible pour les yeux." (Antoine de Saint-Exupéry) "We only well see with the heart, the essential is invisible for the eyes." In memory of Doren Link to comment Share on other sites More sharing options...
fifbrindacier Posted November 18, 2016 Share Posted November 18, 2016 15 hours ago, brus said: Yes,is big about 4cm and found in some mud in Croatia.. Where in Croatia ? "On ne voit bien que par le coeur, l'essentiel est invisible pour les yeux." (Antoine de Saint-Exupéry) "We only well see with the heart, the essential is invisible for the eyes." In memory of Doren Link to comment Share on other sites More sharing options...
Ludwigia Posted November 18, 2016 Share Posted November 18, 2016 The detail's not all that good, but I'm inclined to say rudist now with something attached, either coral or bryozoa. Greetings from the Lake of Constance. Roger http://www.steinkern.de/ Link to comment Share on other sites More sharing options...
brus Posted November 18, 2016 Author Share Posted November 18, 2016 3 hours ago, fifbrindacier said: Where in Croatia ? In south Istra,in a soil not similar whit any other soil in Istra. Link to comment Share on other sites More sharing options...
fifbrindacier Posted November 19, 2016 Share Posted November 19, 2016 Here is a geological map of the peninsula of Istria. It is important if you can locate where you found it, because the rudists lived on reefs from the upper jurassic to the cretaceous at the end of the Maestritchian. If you have found it on a triassic, paleogene or neogene soil, it is not a rudist. "On ne voit bien que par le coeur, l'essentiel est invisible pour les yeux." (Antoine de Saint-Exupéry) "We only well see with the heart, the essential is invisible for the eyes." In memory of Doren Link to comment Share on other sites More sharing options...
abyssunder Posted November 19, 2016 Share Posted November 19, 2016 Looks like a coral, but I'm leaning to a rudist assemblage. (just my opinion) See this thread (for morphology of the external wall and internal longitudinal section) : Sometimes rudist individuals are deformed and/or adhering to each other in the form of bouquet, or juveniles attached to adults; also some of them could be injured but in the regenerating process attached to others, lower valves injured and curved to the siphonal flank or in the opposite direction, etc... A good reference could be DR. Lenke Czabalay biligual edition of the rudist fauna of Sümeg region (Hungary), available Here ; plates in the second (French) version . " We are not separate and independent entities, but like links in a chain, and we could not by any means be what we are without those who went before us and showed us the way. " Thomas Mann My Library Link to comment Share on other sites More sharing options...
brus Posted November 19, 2016 Author Share Posted November 19, 2016 10 hours ago, fifbrindacier said: Here is a geological map of the peninsula of Istria. It is important if you can locate where you found it, because the rudists lived on reefs from the upper jurassic to the cretaceous at the end of the Maestritchian. If you have found it on a triassic, paleogene or neogene soil, it is not a rudist. Hi,i think this map is wrong,couse on south Istra has to be a point whit another color,couse this place looks like a fault...couse the first 2-3m is like everywhere else,but under this is a yellow soil whit rudist and other fossil,and anywhere in Istra is similar soil.tnx. Link to comment Share on other sites More sharing options...
fifbrindacier Posted November 19, 2016 Share Posted November 19, 2016 I don't think so, this just can be a yellow calcareous soil, cretaceous or jurassic, that would explain why there are rudists in it. Maybe two epochs are represented here, or maybe there was a peculiar way of sedimentation in that place that gives this soil its color. Also the map only gives general indications, that doesn't exclude local outcrops. I am not a geologist, but it could be yellow cretaceaous Tuffeau stone, and there is Tuffeau stone in Istrie, here is a link to a document in french on Istria : http://jubilotheque.upmc.fr/fonds-geolhist/GH_000427_006/document.pdf?name=GH_000427_006_pdf.pdf ; Istrie et provinces Illyriennes from P. 93 to P. 104 (the Tuffeau stone is mentioned in P. 98). You'll also find numerous names of fossils here, so if you have books or look for on internet it could help you with your futures finds. "On ne voit bien que par le coeur, l'essentiel est invisible pour les yeux." (Antoine de Saint-Exupéry) "We only well see with the heart, the essential is invisible for the eyes." In memory of Doren Link to comment Share on other sites More sharing options...
abyssunder Posted November 19, 2016 Share Posted November 19, 2016 Those are Cretaceous carbonates. Here are some informations regarding to Istra : Also, here is the document mentioned above : Darko TIBLJAŠ et al. 2004. Mineral and Chemical Composition of Rudist Valves from Upper Cretaceous Limestones of Southern Istria, Croatia. Geologia Croatica 57/1, 73–79. " Turonian to late Santonian limestones of southern Istria are rich in rudist remains. The main aim of this study was to determine the mineral and chemical composition of 22 samples of rudist valves belonging to the genera Durania, Praeradiolites, Radiolites, Gorjanovicia and Vaccinites, and to explain any observed differences. X-ray diffraction and chemical analyses showed that in all the analysed samples, the primary constituents of rudist shells, aragonite and low-Mg calcite, were transformed into diagenetic low-Mg calcite. " " We are not separate and independent entities, but like links in a chain, and we could not by any means be what we are without those who went before us and showed us the way. " Thomas Mann My Library Link to comment Share on other sites More sharing options...
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