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Preserving Shark Teeth


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All,

I have a mix of shark teeth from different localities - Morocco, Bakersfield, South Carolina, etc. Some of the teeth look dry and I am worried they might crumble. I have heard some people apply polyurethane to preserve and provide a sheen while others have told me to use a diluted mix of Elmer's Glue and water. While these coatings may make the fossil look better if I did apply a coating I would want it reversable and I would not want the coating to decrease the specimen value.

What cleaning and preservation process do you all use? What are the pros and cons? What do museums use?

I would like some guidance on this topic.

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I like these products though I use them very sparingly and carefully. It's important to match the specific product to the type of preservation problem you have. http://www.paleobond.com/

I personally wouldn't apply a coating if I thought I'd have to remove it later.

To answer your questions-

1.There are many cleaning and preservation processes available, though for me it depends on the individual tooth.The great majority I simply rinse and let dry.

2.Other members can weigh in on this. For me it's all positive if I can stabilize a tooth.

3.The museums I associate with use a wide variety of products but seem to favor Paleobond products. I'm sure other members have great ideas also.

Screenshot 2024-02-21 at 12.12.00 AM.png

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shark teeth are not all preserved the same. some of them really don't require any consolidation. some of the moroccan ones are fairly fragile.

at any rate, the most reversible stuff is copolymers that dissolve in a solvent like acetone and then do not cross-link or otherwise bond molecularly with the fossil, so that they can be removed with acetone.

sort of - getting anything 100% out of the pores of a very porous material isn't likely. i use PVA beads or PVB powder dissolved in acetone when i want a reversible consolidant.

but almost any consolidant will change the color a bit or otherwise make the fossil look "treated".

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I've tried different things including a few nasty chemicals (toulene for example). The acetone mixes are great with bones but I don't like the plastic sheen they often leave on teeth (your mileage may vary). I finally settled on Elmers and water. It's cheap, it's readily available, it's non-toxic and it seems to neutralize much of the acidity that comes with Phosphate derived teeth (Morocco for example). I once got a collection of someone's teeth from Shark River and the teeth were turning to powder due to high sulfuric content. I tried multiple methods to include the acetones and the root still disintegrated leaving you with a clear plastic cast. The Elmers solidified the root, got rid of the acid and left the teeth feeling like something you had picked up on the beach.

After cleaning the teeth (I use a quick tip in a Sonic jewelry cleaner). I brush the watered down Elmers on the roots. On the enamel, it dries to a dull coat hurting the appearance of the tooth (fortunately you can wash it off) so I only use it on the roots.

Caution on the jewelry cleaner. If you leave the teeth in too long, it will start to damage the roots. And big teeth like megalodons will often soak up water and swell causing cracks in the enamel. And very rarely some teeth are basically held together by dirt (or in the case of some Moroccan teeth, a glue made out of dough) and will fall apart when cleaned.

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I've heard about this happening to Shark River teeth. In fact a lot of NJ fossils suffer from this in some shape or form including historically significant dinosaur and other cretaceous era remains. Do you have any idea how long before you obtained the teeth it took for the process to begin? Or how long did you have them prior to showing signs? I have a lot of these teeth and they are fine so far. But a few that were found as float in the stream show signs of the marcasite/pyrite's disease and I have segregated those or given them away completely. I really don't like the idea of treating sharks teeth, but if thats the only way... I'm more concerned about some of the mammal material anyway.

I've tried different things including a few nasty chemicals (toulene for example). The acetone mixes are great with bones but I don't like the plastic sheen they often leave on teeth (your mileage may vary). I finally settled on Elmers and water. It's cheap, it's readily available, it's non-toxic and it seems to neutralize much of the acidity that comes with Phosphate derived teeth (Morocco for example). I once got a collection of someone's teeth from Shark River and the teeth were turning to powder due to high sulfuric content. I tried multiple methods to include the acetones and the root still disintegrated leaving you with a clear plastic cast. The Elmers solidified the root, got rid of the acid and left the teeth feeling like something you had picked up on the beach.

After cleaning the teeth (I use a quick tip in a Sonic jewelry cleaner). I brush the watered down Elmers on the roots. On the enamel, it dries to a dull coat hurting the appearance of the tooth (fortunately you can wash it off) so I only use it on the roots.

Caution on the jewelry cleaner. If you leave the teeth in too long, it will start to damage the roots. And big teeth like megalodons will often soak up water and swell causing cracks in the enamel. And very rarely some teeth are basically held together by dirt (or in the case of some Moroccan teeth, a glue made out of dough) and will fall apart when cleaned.

---Wie Wasser schleift den Stein, wir steigen und fallen---

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ohhh, i don't even like reading the term "pyrite disease", cuz i'm always afraid my eyes will start turning to dust and it'll migrate to my bwain. as i've stated before, my approach to that stuff is i just don't collect it. may be a huge punt, but it becomes the next guy along's problem.

as far as proprietary white glues used as an aqueous emulsion, i'll say this. first of all, yes i've used them, when stabilizing large and already wet and unstable bone and tooth material. that's all i've used them for. why? well, first of all, i never wet anything with water that isn't already wet, unless it's solid rock. water causes many things to expand and then shrink as they dry, which can exacerbate any problems of delamination or cracking to which the specimen might already be prone. my bias against using proprietary glues isn't that they are not good, but that they are unknown. if the formula isn't released, then you don't really know exactly what all is in it, so its long-term effects and reversability can be in question.

regarding the comments regarding sheen on a tooth - use the solvent to wipe off the sheen.

but at the end of the day, don't worry too much about all this stuff. i mean, i try to be a good "owner" of my things so that they are preserved for later generations, but on the other hand, 86% of people would walk right by all my stuff at a garage sale, even if they had a pocket full of quarters.

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I've heard about this happening to Shark River teeth. In fact a lot of NJ fossils suffer from this in some shape or form including historically significant dinosaur and other cretaceous era remains. Do you have any idea how long before you obtained the teeth it took for the process to begin? Or how long did you have them prior to showing signs? I have a lot of these teeth and they are fine so far. But a few that were found as float in the stream show signs of the marcasite/pyrite's disease and I have segregated those or given them away completely. I really don't like the idea of treating sharks teeth, but if thats the only way... I'm more concerned about some of the mammal material anyway.

I only had them for about a year, the collector had for several years. But even in the few months I had them, they were increasingly falling apart.

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