Brandy Cole Posted October 2, 2021 Share Posted October 2, 2021 I have a few pleistocene bones and large shell fragments that are fractured, and I'm unclear on the best way to repair them. I've read many topics on the forum about the importance of consolidation and materials to use, and I have materials on order, so I should be able to get started soon. But I'm a little unclear on the process if the bone is in two or three pieces. If you have a completely broken bone, should you consolidate the broken pieces separately first (i.e. in an acetone/butvar mix), then glue them back together with something like CA glue? Or would the consolidant make it harder to piece and glue them back together after they dry? Thank you, Brandy Link to comment Share on other sites More sharing options...
Fossildude19 Posted October 2, 2021 Share Posted October 2, 2021 Moved to FOSSIL PREPARATION. @Ptychodus04 Tim - VETERAN SHALE SPLITTER VFOTM --- APRIL - 2015 __________________________________________________ "In every walk with nature one receives far more than he seeks." John Muir ~ ~ ~ ~ ><))))( *> About Me Link to comment Share on other sites More sharing options...
Brandy Cole Posted October 2, 2021 Author Share Posted October 2, 2021 4 hours ago, Fossildude19 said: Moved to FOSSIL PREPARATION. @Ptychodus04 Sorry about that! Thank you. Link to comment Share on other sites More sharing options...
Jasperfossils Posted October 2, 2021 Share Posted October 2, 2021 Hello, Where are the bones from? What is the state of the bones, are they really fragile or not? Link to comment Share on other sites More sharing options...
hadrosauridae Posted October 2, 2021 Share Posted October 2, 2021 Pleistocene material is usually poorly fossilized and therefor very fragile. The first thing you should do is consolidate all the individual parts. What to use for that would depend on the actual state of the bones. If you simply try to glue un-consolidated pieces together, that glue joint will be stronger than the surrounding bone material and it will likely break again beside the join. IF the material is solid enough to withstand submerging in the solution, I recommend that, so it can have time to fully penetrate. If its too fragile and "crumbly" then drip or paint the solution on sections, and keep reapplying until it stop soaking in. Either way, give it several days (preferably under a strong lamp) to fully dry / cure before handling or continuing with gluing or rebuilding. Any excess consolidate on the surface can be removed with a cotton ball with a little acetone on it. "There is no shortage of fossils. There is only a shortage of paleontologists to study them." - Larry Martin Link to comment Share on other sites More sharing options...
Ptychodus04 Posted October 2, 2021 Share Posted October 2, 2021 I agree with the comments above. Pleistocene material is often only partially mineralized and is very soft. If it is relatively stable, I would soak it in a solution of Paraloid (50:1 ratio by weight) until it stops bubbling. Then, take it out of the solution and set it on cardboard to dry. If it sticks, you can remove the cardboard from the pieces with acetone. It will be dry enough to glue together in a day. If possible, use Paraloid as your glue. Mix up a solution at a roughly 10:1 ratio (you’re looking for a consistency a little thicker than honey. Spread this on both sides and stick them together. Support them upright in a box of sand if possible in order to allow the acetone to evaporate without the bones shifting. The acetone in your glue solution will slightly dissolve the Paraloid from your consolidation, providing a really strong bond. If you need a quick set, cyanoacrylate is the go to glue. It isn’t preferable because it is brittle compared to the Paraloid. Photos would be helpful for further advice if you can snap a few. Regards, Kris Global Paleo Services, LLC https://globalpaleoservices.com http://instagram.com/globalpaleoservices http://instagram.com/kris.howe Link to comment Share on other sites More sharing options...
Brandy Cole Posted October 2, 2021 Author Share Posted October 2, 2021 On 10/2/2021 at 3:23 PM, Jasperfossils said: Hello, Where are the bones from? What is the state of the bones, are they really fragile or not? The bones are from southeast Texas. Also a mastodon tusk round and a mammoth tooth plate fragment. Pleistocene material. Most are very solid (camel and equus calcaneum and astragali), but I have a few partial leg bones that are more fragile and a few vertebrae with cracks that look like they could worsen over time if I don't do something. @hadrosauridae Thank you for the advice! My feeling is that most of what I have can stand up to being submerged. (Anything I find here has already survived tumbling through the river a while). But I'll try out test pieces first. I had wondered why some posts mentioned consolidation before gluing, and what you said makes sense. Link to comment Share on other sites More sharing options...
Brandy Cole Posted October 3, 2021 Author Share Posted October 3, 2021 @Ptychodus04 Thank you for the advice! I had seen others recommend a butvar and acetone mixture (or butvar with very high purity alcohol) for Pleistocene fossils on other threads, so I had already ordered some of that, and it's on its way. Is there a substantial difference between the butvar and paraloid that would prevent me from moving forward with the butvar when it arrives this week? Since this is my first try at it, I'm sure I may have a lot of unknown unknowns to deal with. I'm including pictures of the broken equus cannon bone, turtle/tortoise shell fragment, and a very large bone end that I'm still trying to identify. (I'm also including a picture of what it looks like when assembled). The equus and shell are fairly sturdy, but I broke each in accidents while cleaning them. The large unidentified bone is much more brittle and was broken when I found it, so we collected the pieces. They have all been out of water for well over a week and seem completely dry now. Thank you! Brandy Link to comment Share on other sites More sharing options...
Brandy Cole Posted October 3, 2021 Author Share Posted October 3, 2021 @Ptychodus04 @hadrosauridae I should have added that the three bones above are the only ones in pieces that I need to fix. But I'm definitely looking to consolidate all the rest also to help prevent future damage. I'm nervous about all of it, but I was particularly unsure of how to deal with these broken ones. Link to comment Share on other sites More sharing options...
Harry Pristis Posted October 3, 2021 Share Posted October 3, 2021 There are extensive remarks about consolidating bone here: Harry Pristis - The Fossil Forum 1 http://pristis.wix.com/the-demijohn-page What seest thou else In the dark backward and abysm of time? ---Shakespeare, The Tempest Link to comment Share on other sites More sharing options...
hadrosauridae Posted October 3, 2021 Share Posted October 3, 2021 I personally recommend consolidation of all fossils. Youd be amazed at how much a "solid" bone will fracture and crumble from just sitting if its not treated. The only reason to not consolidate is if the piece is going for scientific study. As for the consolidate preference, I dont have one. I'm not an expert, so I cant say if one is particularly better or worse. Each preparator seems to have their own preference. I can tell you that different consolidate plastics can give different sheens to the surface. Some are shiny and others are more dull. One reason that an alcohol solution can be better is if the fossil has previously been repaired with a cyanoacrylate. Acetone will temporarily soften the CA and can cause the repairs to fail (i.e. it falls apart), alcohol will not. 1 "There is no shortage of fossils. There is only a shortage of paleontologists to study them." - Larry Martin Link to comment Share on other sites More sharing options...
Brandy Cole Posted October 3, 2021 Author Share Posted October 3, 2021 @Harry Pristis Thank you! I had seen one of your previous posts on consolidation, which is why I ordered the butvar. I just wasn't sure about consolidating vs repair first and also whether butvar would still be the best choice regardless of fossil condition. Your posts have been super helpful to me as a beginner. Link to comment Share on other sites More sharing options...
Ptychodus04 Posted October 3, 2021 Share Posted October 3, 2021 Butvar and Paraloid are very similar. Paraloid is slightly harder and a little cheaper. Both are soluble in acetone and ethanol. Acetone evaporates faster so will be ready to handle quicker than if you use ethanol for your solvent Regards, Kris Global Paleo Services, LLC https://globalpaleoservices.com http://instagram.com/globalpaleoservices http://instagram.com/kris.howe Link to comment Share on other sites More sharing options...
Brandy Cole Posted October 3, 2021 Author Share Posted October 3, 2021 Just now, Ptychodus04 said: Butvar and Paraloid are very similar. Paraloid is slightly harder and a little cheaper. Both are soluble in acetone and ethanol. Acetone evaporates faster so will be ready to handle quicker than if you use ethanol for your solvent Thank you, that's good to know. Link to comment Share on other sites More sharing options...
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