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Chemicals for prepping
Francesco1994 posted a topic in Fossil PreparationCiao a tutti ! I wanted to have some information about the use of chemicals for the preparation of fossils, let me explain better. I'm currently in my second year of PhD in chemistry and I have a wide range of chemicals, bases, polymer acids etc. My question is what could I use for example to clean the limestone matrix compared to the classic diluted acetic acid? is there anything better that maybe I could have in the lab? I had thought of some stronger acid but I'm afraid that using something stronger could be detrimental to the fossil itself... Grazie !
Questions about chemical preparation
gigantoraptor posted a topic in Fossil PreparationHello all, Me and my friend would like to start practicing chemical preparation. Neither of us have done that before. We were mainly wondering what types of commercially available fossils are fit to practice this on? I know of limestone fossils like Keichousaurus, but that seems quite expensive for a first try. Neither of us lives close enough to a fossil location to reallistically obtain this way. So I tried to make a list of items that are not too hard to find unprepared. My friend has quite a bit of experience with working with chemicals, but doesn't know what chemicals would wo
Lucid_Bot posted a topic in Fossil PreparationHello, forgive me if this question has already been answered. I found dozens of crinoids this last fall. They look great when wet, but when they dry they're dull and dirty looking. I've tried soaking them in soapy water and scrubbing with a toothbrush, but nothing spruces them up. I've also tried using vinegar given that the limestone doesn't fizzle, but it destroys the crinoid. Is there anything I can do to brighten or clean these things? The last two pictures are the crinoids when wet and the first is dry. Thanks for the help.
Keichou - a technical question
Ezio Bonsignore posted a topic in Is It Real? How to Recognize Fossil FabricationsThis question should probably go on the general discussion, but I post it here on the chance that the answer might point at some form of fakety. I am intrigued by this K. being offered fo sale. How was it prepared? To my untrained eye, there seem to be no signs of tools. Judging by the areas surrounding the fossile, it would appear that some kind of acid (?) has been used, thar corroded the stone matrix away while leaving the bones intact (?!?) Is something like that possibile?
Any ways to disaggregate sandstone?
PPorro posted a topic in Fossil PreparationI have read the bits here and elsewhere about DMSO. I'm not that serious and I'm not sure that's what I'd want anyway. Being new and my first post, I hope it's in the right place. I have some sandstone which was a big clump. Fairly beat up from being in Lake Michigan. I looked and decided to crack it open and see what's inside. Now I have a few pieces and I see some interesting fossils, but they look like the same material, nearly, as the surrounding sandstone. I can only guess that if I try to dissolve the sandstone, I'll probably also dissolve the fossils? These look like sh
Mochaccino posted a topic in Is It Real? How to Recognize Fossil FabricationsHello, I'm looking at this ~5cm Ohio Silica Shale Paraspirifer bownockeri. I was wondering if such bright gold coloration indicates "enhancement" of the pyrite by harsh prep, acid treatment or brass wire brush? Or is this just the natural color of some specimens? Many pyritized Paraspirifers I see are more grey or silvery (though I have indeed seen such gold ones). Other pyritized fossils as well seem to typically be more the silver/grey color, and as far as I can tell Pyrite itself is generally paler than a vibrant gold. Thanks.
Crusty_Crab posted a topic in Fossil PreparationI am writing a short manual on preparation methods for our club and I am including a short section on chemical preparation. This is most commonly done with acids on carbonate rocks. For many newbies, chemical preparation is attractive since all you need is a weak acid that everyone has in their kitchen (vinegar or lemon juice) and don't have to buy expensive equipment. I try to avoid it if at all possible since it works on a very narrow class of matrices, you have relatively little control over it, you may dissolve the fossil itself if it hasn't been silicified and its irreversible. Consequent
Cleaning (purple) carbonate from tooth fossils
giftedsifrhippus posted a topic in Questions & AnswersMany of the fossils collected from the Bighorn Basin are coated in this nasty purple-ish carbonate material. I've tried soaking it in a dilute acetic acid but it's not very effective. Would dilute muriatic acid work? Or would it react with hydroxyapatite?
Is it possible to fix this Keichousaurus?
Keimfrei-tanker posted a topic in Fossil PreparationHello community, A friend of mine recently gifted me this keichousaurus. But as you can see the Preperation is not the cleanest/nicest. Can I as an amateur fix this by myself or make it look cleaner and nicer? I also had the Idea that I maybe could work from the other side with Acid layer by layer. Then I could also be able to see the upper side of the specimen rather than its belly. Or would that not work/ be to risky? Isbthe rock maybe to thin? Can i as an amateur who never worked on a fossil with acid before make that or is it generally not possible?
ParkerPaleo posted a topic in Fossil PreparationThis could possibly be a random incoherent thought bubble, but here goes anyway. I was reading another thread which mentioned acid prep as the way to go for a particular item and then was proceeded by a bunch of professional preparators (that I repsect) being scared of the prospect of attempting it themselves. This really bothered me. I know I have a wealth of experience preparing far surpassing what a normal fossil aficionado would have, and I have always thought of acid as a tool in my bag and not something to be scared of. I am not a professional preparator, though
For you Brachiopoders- Don’t try this at home please.
LabRatKing posted a topic in General Fossil DiscussionOkay gang. Don’t ever do this. Brachs are so common here ( along with crinoid bits) I use them as aquarium gravel... But, here’s what happens when you figure out how to acid prep Kewitz limestone to expose calcite and not loose morphology: I finish these with a week long silicon oil soak to make them shine.
removing matrix (sandstone/limestone) safely
OregonFossil posted a topic in Fossil PreparationSo, what is the safest way to remove matrix (sandstone and limestone) from calcium shelled fossils. Everything I've read involved acids (some pretty dangerous). What is most ecologically friendly and safest way? I have picks and dramel , but these shells are very thin and almost impossible to remove from the matrix. I am thinking that weaker acids might not work that well and the costs of using more powerful stuff would require a special room with exhaust systems and ways to neutralize the stronger acids to make them environmentally safe. Images are typical of fossils I want to extract.
2 more Halysites 'chain coral' from Silurian in Wisconsin, acid treatment
traveltip1 posted a topic in Fossil Hunting TripsHere are 2 more Halysites 'chain coral' that I found in the Silurian of Wisconsin. The rocks were soaked in diluted muriatic acid for several hours, to partially dissolve the matrix and reveal the chain corals.
Silurian - crinoid vertebra?
SteveE posted a topic in Fossil IDCentral PA, Mifflintown-Bloomsburg (undividied) Block collected from roadsite float. Its pretty variable, with a flaky/fissile layers alternating with slightly more cohesive ones. Lots of broken brachiopod bits. For an experiment to I dropped an unremarkable flake the size of a large coin in some vinegar and let it soak for a day. The flake had a couple brachiopod bits and I wanted to see if they would fall free or dissolve in place. The brachiopds disappeared and I was left with this (see pics). Of course I got really excited and thought I had an early fish spine, but now I thin
What should I buy to start testing my specimens...
InfoHungryMom posted a topic in Questions & AnswersI have zillions of rocks/shells/fossils/pieces of bone, etc. I am not a chemist, and I do not want to get into anything unnecessarily dangerous/toxic. Also, I would love to possibly cut and polish rocks that I find fascinating. What do I need for my “starter kit”, and can you/will you please recommend sources for these items that you work with, and that you like and trust (especially a source with great patience to answer the tons of questions I will have). Thank you- Karen
chemical 'bloom' on fossil - ?
Wrangellian posted a topic in General Fossil Discussion(Not sure of the tags I should use.) This is the first instance I've found of any sort of 'bloom' on a fossil in my collection. Luckily it's not the best specimen but it is an echinoid and they are not as easy to find here as in some other places. Sandstone from the Haslam(?) Fm on Vancouver Island. Is this a calcitic bloom from some sort of acid or off-gassing from something in my storage media? I'm not sure how long this has been in this condition but I think it's happened within the last 10 years. I'm trying to keep things away from my collection that might cause this sort of
Captorhinus aguti prep
PalaeoArt posted a topic in Fossil PreparationHi Fossil Forum, I've recently picked up a unprepped skull of Captorhinus aguti, from Olkahoma and am looking to do some further delicate prep. I've not used acid preparation before on such a delicate specimen (such as Muriatic acid) - could anyone who has give some advice about application, duration and dilution levels? Many thanks Tom
Buffering acetic acid
OctoDude posted a topic in Fossil PreparationHello, Long time occasional lurker, first time poster; I hope this is the appropriate place and method for posing this question, and I apologize if it is not! I have some limestone blocks containing conodont teeth and shark teeth, which I would like to break down with acetic acid. From what I have read, adding a buffer to the acid solution would greatly help in preventing damage to the teeth (and especially the roots), but I have no idea what buffers are readily available (and from where they would be available) and commonly used (and how much is needed). Can anyone a
Can You Clean Fossils With Acid ?
matthew textor posted a topic in Questions & AnswersHi this is Matthew my question is can you use acid to clean fossils and what kind should I use ? and does anyone know how to do it correctly ? and thank-you