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I found this ammonite on Saturday. It is the best Trachyscaphites springer I have ever found. I think it is a T. springer. I assume the other ones I have are males and maybe this one is a female. I don't know much about sexual dimorphism in this genus, but it does exist. When they say there is dimorphism is the female is bigger? It is so very different from any of the others I have. I know there is another species of Trachyscaphites in the NSR, but I don't know what it looks like. I really like this one though. It is free standing too! Bonus. It has some damage on the dorsal venter and the aperture. It also had some pyrite on the umbilicus area (I can’t really see an overt umbilicus since it is so involuted). My prep work is still very crude. There is so much I need to learn. I just keep at it and learn by trial and error though. I don’t have pneumatic tools. Here it is. See the white film on the right half? The white on the left half is nacre, but some of it has the film on it too. This is from the red zone of the Ozan formation, Cretaceous. I doubt it matters, but I am wondering if the film layer is pyrite in nature or gypsum or something else. I have specimens from the Britton formation of the Eagle Ford group, which have a gypsum film on them and this looks a bit little that. But that isn't my main question. It is just a curiosity. This is the other side. You can see some pyrite at the bottom left along the umbilicus grove. I have a number of these, but this is the first where I can actually see suture lines mostly at 11 to 12 o'clock down the midline and on the right. I am going to tag @Ptychodus04 and @RJB on this. I don't know if Ron is familiar with fossils of this matrial and matrix, but I imagine he is. I am pretty sure Kris is. Questions The film issue 1. Do you think I should attempt to remove the film? I think I should. See the tubercle by my thumb in pic 2? There was a tiny fleck of white showing so I chipped away at the red clay and revealed more nacre under it. So I believe there is still nacre under some of it on the left 2. What is the best way to go about removing it? I was thinking of using sandpaper, but I don't have much experience using sandpaper on fossils. I have a range of grit up to 3000 (or is it down to since the grit is smaller and finer?) The nose issue I am calling it the nose since it looks like a little nose. It seems to be the first part of the first visible whorl. 3. Any advice as to what to do with this part. I am not sure what to do with it. At times I prep haphazardly and then I think I have damaged it and I get paralysis of analysis and that is where I am on the nose. I have removed some matrix from the top, left and right. I think I might have gone down into the nose on the right side some. It is hard to tell where the matrix ends and fossil begins. These are other views of the nose. The lines on the nose are from me scraping away, thinking I was on top of ribs. I am not sure if there are ribs there yet. Like I said my prep skills are pretty crude still. The other side of it. I still have some matrix to removed on the side there. I think part of it is chipped away, but I am not totally sure how it is supposed to look. Maybe it got crushed. It just looks odd to me. I have several other of this species, but I think they may all be males or something. They are more open, the whorl does not cover the umbilicus and they are much flatter and smaller. The pyrite issue. I know I have asked these types of questions before about prep so sorry for the repeat. 4. What is the best way to address the pyrite to keep it from coming back? I have scraped most of it off already. I have heard people say to soak it in Iron Out and I have that. But I am concerned it may hurt the fossil. I guess I could experiment on other concretions I have that look like the same, but are rock and not fossil. 5. What should I do as far as long term preservation to slow the progress of pyrite disease? I think someone recommended Butvar. I looked into buying it, but I got sidetracked by trying to figure out which was best. Then couldn't find what was best and kind of forgot about buying again. 6. What is the best Butvar or product to use for sealing it? I looked at buying some on different sites. Paying so much for shipping irks me. I am spoiled with Amazon Prime and just don't think about shipping costs. I have a buddy who works at Eastman. I asked him if they had a store where individuals could purchase products like Butvar 76. He said no, but he would see if he could go ask for a sample The museum supply site. It has Butvar-80 for $34 for 1 kg and $15.53 for shipping. I don’t need 1 kg. Talas has Butvar-76 500 g for $17.50, but then is charging $14.64 for shipping! I have seen people reference McGean-15 or Vinac and they seemed to prefer it over Butvar. 7. Can anyone tell me the molecular weight of the Vinac or what grade of polyvinyl acetate Vinac is? I think my buddy could come up with that for me more easily since I think he manages production of a form of it. I found something called Vinapas. I have not looked at the shipping on this site. Here: http://www.conservationresources.com/Main/section_37/section37_08.htm PVA Resin Solid Vinapas This consolidant is a polyvinyl acetate solid suspended in granular form, with a molecular weight averaging 51,000 and a melting point of 50 C. It is used as a consolidantfor porous, dry, non-metal objects-particularly those found in digs. This is typically applied in concentrations of 20-25% I.M.S. with a soft brush. It may also be used as an isolating varnish and thermoplastic adhesive. Item # Description Price SY01 Vinapas, 1 kg. $22.00

Creek was a little flooded today made it harder to navigate, started the day with 2 dead drill battery's that I had charged the night before so I decided to move father up to look at some different exposures, started by picking up some matrix for micro's from the bottom of the pecan gap, more on that later, and then some Del Rio clay for the same, (if someone has suggestions for how to wash this faster that would be great) spent the next 2 hours picking up heteromorph mariellas.

I have been mostly caving in Colombia but stopped on a mountain creek to mess around for about 20mins. I need to get more pics of our haul but this is pretty cool (or I think so)

A while ago I bought this tiny gault clay ammonite preserved in pyrite and in a few months of storage next to dessicant mineral these strange white crystals have grown. -pyrite disease?