gieserguy Posted January 22, 2020 Share Posted January 22, 2020 I found this strange Composita subtilita at the Paleo Site bear Kohls Ranch, Arizona. It is from the Middle Pennsylvanian Naco Formation. Does anyone know what’s going on with the strange pattern? Flip side I also should be able to provide slightly higher quality photos if needed, I just reduced the quality to be able to post several PS-I wasn’t sure if I should post this here since I have an ID, so please move it if it shouldn’t be 3 Link to post Share on other sites
Petalodus12 Posted January 22, 2020 Share Posted January 22, 2020 Looks like the structural support for the lophophore, the brachiopod’s feeding apparatus, has been preserved. I believe this is called the brachidium but I am not sure. Very cool find. 8 Link to post Share on other sites
DPS Ammonite Posted January 22, 2020 Share Posted January 22, 2020 Petalodus12 is correct. Keep it, it is a good piece. http://www.kgs.ku.edu/Publications/ancient/f14_spirif.html 4 Link to post Share on other sites
gieserguy Posted January 22, 2020 Author Share Posted January 22, 2020 @Petalodus12 @DPS Ammonite Oh wow thank you both so much! It's quite nice to have another reason to love this fossil, considering I liked it because it looked quite H.R. Giger -esque haha! Link to post Share on other sites
DPS Ammonite Posted January 22, 2020 Share Posted January 22, 2020 5 minutes ago, gieserguy said: It's quite nice to have another reason to love this fossil, considering I liked it because it looked quite H.R. Giger -esque haha! Link to post Share on other sites
connorp Posted January 22, 2020 Share Posted January 22, 2020 @gieserguy If you let Composita from the Oglesby roadcut sit in vinegar for a short while, just enough to dissolve the outer layer, you can see these structures as well. Probably would work for Composita from elsewhere as well. 1 Link to post Share on other sites
gieserguy Posted January 22, 2020 Author Share Posted January 22, 2020 2 minutes ago, connorp said: @gieserguy If you let Composita from the Oglesby roadcut sit in vinegar for a short while, just enough to dissolve the outer layer, you can see these structures as well. Probably would work for Composita from elsewhere as well. Oh, interesting! I'll have to try that when I'm home next, I certainly have enough Composita from Oglesby to try it on. I guess I was just lucky enough to find one that had already been weathered away just enough to see the inside structure. I know the rock at Oglesby is limestone, but I guess I never really thought that the fossils were also preserved in limestone. Link to post Share on other sites
connorp Posted January 22, 2020 Share Posted January 22, 2020 22 minutes ago, gieserguy said: Oh, interesting! I'll have to try that when I'm home next, I certainly have enough Composita from Oglesby to try it on. I guess I was just lucky enough to find one that had already been weathered away just enough to see the inside structure. I know the rock at Oglesby is limestone, but I guess I never really thought that the fossils were also preserved in limestone. The Composita at least are silicified. But if you place them loose in vinegar, there's no limestone to act as a buffer so the vinegar will degrade the shells. 1 Link to post Share on other sites
gieserguy Posted January 22, 2020 Author Share Posted January 22, 2020 Just now, connorp said: The Composita at least are silicified. But if you place them loose in vinegar, there's no limestone to act as a buffer so the vinegar will degrade the shells. Ahhh gotcha, that makes sense. I haven't looked much into acid prep so I only know the very base info on it. I have some big chunks from Oglesby that I could play with a little acid prep on as well. I think you might have just given me some spring break ideas Link to post Share on other sites
westcoast Posted January 22, 2020 Share Posted January 22, 2020 Very nice find. There are not many places where you get brachidium preservation like that. Congrats 1 Link to post Share on other sites
gieserguy Posted January 22, 2020 Author Share Posted January 22, 2020 2 minutes ago, westcoast said: Very nice find. There are not many places where you get brachidium preservation like that. Congrats Thank you! I appreciate it, I'm quite happy with this little beauty Link to post Share on other sites
connorp Posted January 22, 2020 Share Posted January 22, 2020 13 minutes ago, gieserguy said: Ahhh gotcha, that makes sense. I haven't looked much into acid prep so I only know the very base info on it. I have some big chunks from Oglesby that I could play with a little acid prep on as well. I think you might have just given me some spring break ideas I've used it with moderate success on the fish bits from there. Vinegar won't destroy the fossils directly, but if a fossil is very thin the vinegar can compromise the limestone underneath and in any cracks and cause the fossil to break up. This is pretty common with the petalodont bits. But a lot of times an engraver is too aggressive, and without any air unit, vinegar is really your best bet. 1 Link to post Share on other sites
Peat Burns Posted January 22, 2020 Share Posted January 22, 2020 54 minutes ago, connorp said: @gieserguy If you let Composita from the Oglesby roadcut sit in vinegar for a short while, just enough to dissolve the outer layer, you can see these structures as well. Probably would work for Composita from elsewhere as well. Wait, what?! I'm gonna get on that tonight. I don't know how many hundreds (thousands?) of brachs I've collected, and I have yet to find a preserved brachidium. I'm going be bathing in acetic acid tonight thanks to @Nimravis (oglesby brachs) Link to post Share on other sites
connorp Posted January 22, 2020 Share Posted January 22, 2020 2 minutes ago, Peat Burns said: Wait, what?! I'm gonna get on that tonight. I don't know how many hundreds (thousands?) of brachs I've collected, and I have yet to find a preserved brachidium. I'm going be bathing in acetic acid tonight thanks to @Nimravis (oglesby brachs) Oh gosh now I'm feeling some pressure. I haven't done this in a year or so, so I might be remembering incorrectly. Tossing some in now to check 1 Link to post Share on other sites
gieserguy Posted January 22, 2020 Author Share Posted January 22, 2020 Just now, connorp said: Oh gosh now I'm feeling some pressure. I haven't done this in a year or so, so I might be remembering incorrectly. Tossing some in now to check Make sure to post em here! I'm excited to see how they turn out Link to post Share on other sites
Nimravis Posted January 23, 2020 Share Posted January 23, 2020 4 hours ago, Peat Burns said: Wait, what?! I'm gonna get on that tonight. I don't know how many hundreds (thousands?) of brachs I've collected, and I have yet to find a preserved brachidium. I'm going be bathing in acetic acid tonight thanks to @Nimravis (oglesby brachs) Okay I tried it and nothing happened, oh well. Before- After- 2 Link to post Share on other sites
connorp Posted January 23, 2020 Share Posted January 23, 2020 This took about 4 hours in vinegar. And I do take back that these are silicified, I don't think they are. 3 Link to post Share on other sites
Nimravis Posted January 23, 2020 Share Posted January 23, 2020 11 hours ago, connorp said: This took about 4 hours in vinegar. And I do take back that these are silicified, I don't think they are. I am going to re-due and leave them overnight. 1 Link to post Share on other sites
DPS Ammonite Posted January 23, 2020 Share Posted January 23, 2020 Look for the broken reddish silicified Compositas that occur in the Naco Fm. near Payson. When cleaned in HCl the brachidium are incredible. 4 Link to post Share on other sites
Peat Burns Posted January 23, 2020 Share Posted January 23, 2020 1 hour ago, Nimravis said: Okay I tried it and nothing happened, oh well. 1 hour ago, connorp said: This took about 4 hours in vinegar. And I do take back that these are silicified, I don't think they are. 14 minutes ago, Nimravis said: I am going to re-due and leave them overnight. I'm going to use my aquarium fish disease philosophy: "cure it or kill it" and use whatever acid strength necessary to get results 2 Link to post Share on other sites
Peat Burns Posted January 23, 2020 Share Posted January 23, 2020 10 hours ago, DPS Ammonite said: Look for the broken reddish silicified Compositas that occur in the Naco Fm. near Payson. When cleaned in HCl the brachidium are incredible. 1 Link to post Share on other sites
DPS Ammonite Posted January 23, 2020 Share Posted January 23, 2020 Sometimes the silicified broken Naco Fm. brachiopods hold other treasures. 5 Link to post Share on other sites
gieserguy Posted January 23, 2020 Author Share Posted January 23, 2020 10 hours ago, DPS Ammonite said: Look for the broken reddish silicified Compositas that occur in the Naco Fm. near Payson. When cleaned in HCl the brachidium are incredible. Wow those are stunning! The red coloration just adds to the beauty. You said near Payson, were these collected at the “Paleo Site” near the Kohls Ranch exit? Link to post Share on other sites
DPS Ammonite Posted January 23, 2020 Share Posted January 23, 2020 10 minutes ago, gieserguy said: Wow those are stunning! The red coloration just adds to the beauty. You said near Payson, were these collected at the “Paleo Site” near the Kohls Ranch exit? I have not found any at the Paleo site; those are mostly not silicified. The silicified brachiopods occur in isolated spots in the lower Naco Fm. from Pine east to the Apache Reservation. A friend found some of these near Christopher Creek. 1 Link to post Share on other sites
Nimravis Posted January 23, 2020 Share Posted January 23, 2020 Here are the results that I thought would happen by leaving them over night- destroyed 1 ok and 2 very nice Compositas from Olgesby, Illinois. 1 Link to post Share on other sites
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