Kem Kem Jaw Autopsy

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Hi
Some time ago a postet a jaw from the Kem Kem in the "is it real" section. The jaw obviously had some repairs using the typical sand/glue material. However, it was not 100% clear to what level the jaw has been repaired/altered/faked. I am a scientist (but not a palentologist) and I did not want that uncertainty.  Therefore, I decided to test our conclusions by removing the sand/glue mixture using an airscribe (Paleotools ME 9100). I thought I post the results here as potentially useful educational material. Maybe it helps you guys when buying material from Morocco.

 

This is how the jaw looked like prior to the prep. When removing the sand with the airscribe, the difference between natural matrix (compressed sand) and artificial matrix (sand/glue mixture) is VERY obvious. The natural matrix comes off easily and seperates very well from the fossilized bone. The sand/glue mixture is much stronger and adheres to the bone.

 

blue color: natural matrix (compressed sand)
red color: artifical matrix (sand/glue mixture)

 

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This is how the jaw lookes like after the autopsy. I removed all sand from the bone.

 

 

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Conclusions:
- The autopsy confirmes that the large tooth as well as the broken tooth have been assembled into the jaw (this is common practice).
- For the small unerrupted tooth I did not find evidence that there is something wrong so it probably belongs to the jaw.
 

In case you plan to do something similar with your Kem Kem fossils:
-  Natural matrix can be easily removed, even with a hand-pick.

- The sand/glue mixture cannot be removed with a hand-pick. In my case at least it was to hard.
- When remving sand/glue mixture with an airscribe use it in a very flat angle to the bone. Otherwise to much energy will be induced into the bone and you will damage it. 

[LordTrilobite]

Good topic. Quite informative to see the before and after. Thanks for sharing.

[Tidgy's Dad]

Very useful thread.

Thanks for sharing. 

I think it the jaw looks better in it's natural state anyway. 

[Flx]

1 hour ago, Tidgy's Dad said:

I think it the jaw looks better in it's natural state anyway. 

 

Yes, I agree. The natural state looks better. 

[Troodon]

Very nice, thanks for sharing always good to show others what can happen with jaws. 

[Bone guy]

Just out of curiosity is this a croc or theropod jaw? 

[Haravex]

Very nice in depth analysis, however one thing I would recommend is that using acetone on a piece like this will help remove the sand matrix glop and this in turn helps ensure the fossil receives less damage. If however you suspect the bone is fragile or shows signs of this weaken the super glue glop with a 5% percent paraloid to acetone solution this I do for one very good reason in morocco the heat is so much that the super glue dries very fast this means it does not penetrate the bone where as this will and will soften the superglue on the surface.

[Flx]

10 hours ago, Bone guy said:

Just out of curiosity is this a croc or theropod jaw? 

 

I think there is not enough material published to say for sure.

Currently, I am leaning towards spinosaurid. The crocodile material I have seen so far looks quite different.

[Flx]

10 hours ago, Haravex said:

Very nice in depth analysis, however one thing I would recommend is that using acetone on a piece like this will help remove the sand matrix glop and this in turn helps ensure the fossil receives less damage. If however you suspect the bone is fragile or shows signs of this weaken the super glue glop with a 5% percent paraloid to acetone solution this I do for one very good reason in morocco the heat is so much that the super glue dries very fast this means it does not penetrate the bone where as this will and will soften the superglue on the surface.

 

Thanks for the suggestions. I will give it a try next time.