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Hello again! I have done my first experiment with Butvar 76 after drying my Green River fish fossils for 15 days. For this first experiment I selected a thin partially complete Diplomystus from the lower quality end of my haul last month. I gently blew compressed air over the fossil which had been picked lightly with a dental tool, then applied my mix of Butvar-76 and acetone. I found different recommendations for the ratio, and probably used to much powder in my solution because as you can see, upon returning from work I found that small bubbles were trapped inside. I assume the surface tension was too high to allow them to escape as a result of using too thick Butvar. For my next experiment I will thin it out, and brush on thin coats and apply them one at a time instead of thickly applying it. I also noticed that some of the stone dust washed into the solution above the fossils midsection in the depressions between the thin bones. Feel free to critique my first attempt and give any advice.

I have started prepping Green River fish for one of the quarries in Kemmerer and one of their requirements was that I switch to using iron powder for my abrasive. It's expensive but I wish I had done this years ago! It took a fair bit of cleaning to get the baking soda out of my dust collection system (you don't really want them mixing together). Iron powder is slightly harder than soda but is more rounded. It removes the matrix really quickly with less damage to the specimen. I can operate at significantly lower pressures as well. The softer bits of matrix come off easily at 8 psi. Another aspect of the iron powder is that it is easily recoverable with a magnet in a bag. about 50% drops in the box. I pick it up with the magnet, sift it through a 100 micron sieve and dump it back into the abrasive hopper. My dust collector dumps into a bucket to collect the heavy/large particles on the way to the fines bag. This grabs about 90% of the abrasive that gets picked up by the suction. I have another magnet in the bucket that gathers most of the iron and every 4 or 5 hours of work time, I open the bucket and recover the abrasive. This gets sifted and goes back into service.

Hi everyone, I got this fish at a mineral shop and he had no identification for it. My son thought it might be a knightia or a mioplosus. It also looks to me like it got fossilized when going to the bathroom. Can anyone help me ID it? Am I right about the poop? I'd really appreciate it. Pat

Hello, I'm about to start my first experiment in preparing an Eocene fish from the Green River 18 inch layer. I've done some prep of fish from the "split fish" layer with some success. But the matrix here appears much different! I'll be doing with with a pin vice, scribe and a head band magnifier with good lighting. I could use any advice from y'all with MUCH more experience than me! Thanks

Hi all, it's my first green river fossil fish prep, i think head preped out ok, but before I start with the rest, since there are some very experience Green river preparators here, I would appreciate any tips how to preserve soft tissue parts (between ribs i.e.)!? Thank you in advance! Hope to save as much soft tissue as possible, like in example below (not sure if any colour enhancements though?). Downloaded this pic from fossilrealm web:

Hello everyone, I'm looking for a second opinion on this piece, a fish head from the green river fauna, while I believe it maybe Amia due to comparisons I'm not to confident, any help/guidance is and will be appreciated.

Hey all, I have a Green River fish I purchased many years ago. The bones mostly seem well preserved, but the fins at least (and likely all of it) was painted a dark brown and then some sort of a sealant was applied. The matrix is different from the usual split fish material, it is more like a hard sandstone (much more sturdy than the split fish layer) and it is a brownish color. Likely the fish was painted to "improve" contrast with the dark matrix. I would like to remove the paint and restore the fish to its natural condition. I have soaked it in acetone for hours (in a fume hood of course) and that removed the sealant but the paint is almost untouched. Does anyone know what kind of paint commercial dealers use (or used to use 30 years ago) and how to remove it? Don

When I was at the Tucson fossil show I picked up several slabs of unprepared Green River fish from the 18-inch layer. I've been working on this Knightia and have a few questions. I only have hand tools so I have been carefully removing matrix using some pin vises with various needle tools I picked up from PaleoTools. Here's how it looks so far: First question: If you look in the areas of the anal fin and the dorsal fin, there appear to be random swatches of organic material not associated with the body. Perhaps these are regions that "blew up" as the fish was decomposing. Should I be removing these and trying to restore the original outline of the fish or should I leave them alone? For example, here's a closeup of the dorsal area: Next question. It's been difficult to remove all the last bits of matrix with needle tools. The photo below shows the bits of matrix remaining in areas around the backbone. I don't think I can do much more on it with needles. Would it help if I were to invest in something like a Paasche AECR air abrasive tool or should I stop here. I would need a compressor, blast cabinet, and all the paraphernalia if I were to do this, but if it would help I might consider it.

As I mentioned in a previous post, when I was at the Tucson Fossil Show I picked up some unprepared slabs of Green River Fish from the 18” layer. That prompted some of you to say you expected me to post photos as I did the prep work. I initially rejected that idea because I’m pretty bad at prepping and I didn’t want to post pictures showing how bad I am. But then I remembered some advice I once got from a manager I reported to early in my career. After I made an engineering decision that didn’t turn out so well, he told me, “It looks like your fate in life is to serve as the bad example everyone else learns from.” That cheery sentiment was underscored by this framed inspirational poster he had hanging on his office wall: So with that in mind, I decided to go ahead and post photos of my prep work, not to show you how to do it, but rather to give you the bad example everyone else can learn from. I picked up a total of four slabs, but the one I will show you in this and subsequent posts is one that was claimed to be a Priscacara species. Of course you don’t know for sure until you do the prep, but I wouldn’t be surprised if they had done some sort of X-ray before they put the slabs out for sale to make sure they weren’t selling a rare specimen for a dirt-cheap price. In any event I’ve been happy with the specimen, even if the quality of the prep could be better (this is my first time prepping a specimen from the 18" layer). I actually started the initial prep while still in my hotel room in Tucson, but I don't have a photo of this fish from there. Here's a photo of one of the other slabs to give you an idea of what they looked like. The seller drew a bunch of lines in pencil to show what he thought was the outline of the fish, so that's mostly what you are seeing here. It was a lot easier to prep once I got it home. I only have manual scribes so it is a very slow process. Here’s a photo of my setup. I’m convinced I would not be able to do this without the microscope, which I keep at the lowest setting, 6X. I have 3 probe tips, all purchased from Paleotools when I was at the show. I also bought two pin vises to go along with the one I already had. Of the probe tips, one is oval, one is flat like a flat-head screwdriver, and one is a sharp point. With my technique I have found the oval probe to be the most useful, followed by the flat tip. I only use the pointy one to do delicate cleanup in tight spots. To keep the dust from getting all over the place I mostly use the yellow brush to clean it off and save the blower for critical spots. Even then I don't use it at anywhere near full blast power. Even so, you can see it's already covered in dust. Here’s how it looks after about 5 hours of prep (I said it was a very slow process!). The tail looks like it has been blown up, probably due to decomposition before being covered with silt. The ribs are looking pretty good except for at least one that’s far out of position and pointing in a completely different direction than the rest. Looks like it has 9 dorsal spine rays, which is consistent with Priscacara serrata. The areas around the pelvic fin and where the caudal rays branch from the body were prepped by the seller, probably with air abrasion, I assume to help sell the specimen. Here it is after about another 3 hours, mostly to expose the anal rays and further clean up the dorsal spines. It has 3 anal spine rays, further confirming it identification. You can see my favorite probe tip on the left. Next up is to start working on the head, which will be more difficult because the matrix covering it is a lot thicker. This fish is definitely from the 18” layer, as the smell of petroleum is pretty strong. I’m finding I can only work for about half an hour at a time, two or three times a day. If I work longer, I get nauseous and get a headache that doesn’t go away for a day. So this is making the prep go even slower. I did a search on the TFF forum for other threads on prepping Priscacara from the 18” layer and found a good one from back in 2017, in which @Ptychodus04 recommended dampening the matrix to soften it. I have been doing this and it not only softens the matrix it also keeps down the dust and fumes. And it adds contrast when I take photos. Good idea! Here’s where I am at now, after about another 5 hours of work. The head is starting to emerge, but I have to say I can’t identify any of its features when I compare them to the photos from Lance Grande’s book, The Lost World of Fossil Lake. Not sure what is going on here, I’m open to suggestions. Meanwhile I will keep plugging away and post occasional updates as I have them. What are these bones?

I purchased the following fish plate from the Warfield Fish Quarry gift shop while on a family fossil fish dig many years ago. It looks to be a mid-sized diplomystus (about 8 inches long) swallowing a knightia. The unusual thing about this situation is that the knightia seems to have been caught tail-first!? I have never seen this before... I would like some expert opinions on whether this is an unusual aspiration or if it's just a mega coincidence where two fishes happen to be preserved overlapped in just the right position to appear that way. Any feedback would be appreciated. Thanks.

I've finally gotten around to prepping some Green River fish I dug from Warfield Fossil Quarry about 10 years ago. I've identified several of them as a specific Knightia species, but I'm not sure of the correct species name. According to Paleontology of the Green River Formation, with a Review of the Fish Fauna," Geological Survey of Wyoming Bulletin 63, by Gary Glass, published in 1984, the correct identification is Knightia humilis, with K. eocaena being a junior homonym. But according to A Revision of the Fossil Genus Knightia, With a Description of a New Genus from the Green River Formation, by Lance Grande and published 2 years earlier, K. humilis is the junior homonym and K. eocaena is the valid name for the species. I've searched this forum and found both names used. Can someone tell me what is currently considered the correct name? (Sorry I've had to insert links rather than add the actual documents, they are both too large to attach here.)

I've been sorting through some fossil fish I dug on a trip to Kemmerer, Wyoming (Warfield fossil quarry) about 10 years ago. All my specimens were taken from the split-fish layer. I discovered this piece I had wrapped up that day and never uncovered until now. Referring to my copy of Gary Glass's Paleontology of the Green River Formation, Bulletin 63, I have tentatively ID'd the one full fish as a Diplomystus dentatus, primarily because of the extended anal fin (I count about 38 anal rays, it's a little hard to tell for sure). I know it's on the small side, but am I correct? As for the two partials, I don't know, unless we use "guilt by association" to assume they are the same. What do you think? I'm thinking about mounting this slab on an oval-shaped piece of oak for display. Fossils from the split-fish layer are notoriously fragile, pieces of bone break off easily. Should I coat this with something for protection? I've read about Paraloid B72, Elmer's glue, etc., but haven't used any of them. Any recommendations?

Prep was just finished on this lovely panel. All three fish are 100% natural. NO INLAY! NO PAINT! Wonderful panel with three fish. Notongoneous (long skinny guy) Diplomystus (big fat one) Priscacara (spiny one) This panel measures 34 inches tall x 45 inches wide.

Found this strange looking object near the tail of a Green River Priscacera that I'm working on. Curious as to what it might be. It almost appears attached to the fish. Any thoughts?

I had bought a handful unprepped Green river fish last week from a fellow member (Thanks Ron). The goodie package arrived Saturday morning. But all of Saturday was a crazy mess due to my girlfriend's twins birthday party. And anyone that knows trying to handle 8+ nine year olds is just short of hair pulling madness, especially when my gf decided to hop them up on a buffet of candy. So i didn't even get the chance to open the package..... Sunday i slept in (it was justified), but i remembered my box of fish. The gf and the kids were off shopping with their bday money and my 16 month old son was at Grandma and Grandpa's house, so yeah it was a joyous day of laziness. So i decided to prep out some fish. I started with the two smallest just to get a feel for it. I simply used an upholstery needle and toothbrush for the prep. I later "enhanced" them a bit were the fish bits had flaked off on me using watered down acrylic paints. Slow and steady definitely wins this race. One fish the face wasn't fully intact, so i had to make due. They're not the best, but they sure are fun to do! Edit: This is highly recommended for any amateur fossil enthusiast. No expensive prep tools are needed. And sorry i regretfully didn't take any before pics. They basically were covered in matrix. The only sign of them was a raised line (vertebrae) and a faint outline of fins and the heads. I'll take before and after pics of my other larger ones.