Mosasaurus Jaw, double-checking authenticity ;)

[FossilSniper]

I decided to (finally) spend some money and buy a mosasaur jaw section- my first jaw!
I know that there are many fabricated mosasaur jaw sections out there, but I have ascertained for myself that this one is nothing to worry about.
However, I still think that if there are indeed any problems with it, expert input would not hurt at all.
Maybe I could even attempt extraction! (with the the proper methods, of course.) 
I really prefer fossils outside of their matrix- I am never content with 1/2 of a fossil while the rest remains entombed inside.

Behold! 
Halisaurus (arambourgi?) Jaw section

The section is 8.89 centimeters in length, and 3.17 centimeters in height (crown tip to the bottom of jaw)

Found in: "phosphate mine region, Khouribga, Morocco." I wish they could be more specific.

This would make a fine addition to my currently expanding collection.
Thank you all for your input!

If anybody is brave enough to figure out what part of the jaw this is from, that would be fantastic as well.

[Aurelius]

The picture isn't super-high resolution, but it looks fine. It's a bit more expensive than I'd like to pay myself, but for a retail price it's fine, and a good piece. 

 

Sometimes I like jaws in the block, and sometimes I like them out. I think this will look better when extracted, because we're only seeing the inside of the jaw at the moment, which isn't as attractive. 

[FossilSniper]

19 minutes ago, Aurelius said:

The picture isn't super-high resolution, but it looks fine. It's a bit more expensive than I'd like to pay myself, but for a retail price it's fine, and a good piece. 

 

Sometimes I like jaws in the block, and sometimes I like them out. I think this will look better when extracted, because we're only seeing the inside of the jaw at the moment, which isn't as attractive. 

I agree. I wish the picture was higher quality.
Do you have any suggestions on what tools to use with moroccan matrix?
I know the material is very easy to work with, but I additionally do not want to attack the matrix too roughly.

[Aurelius]

1 minute ago, FossilSniper said:

I agree. I wish the picture was higher quality.
Do you have any suggestions on what tools to use with moroccan matrix?
I know the material is very easy to work with, but I additionally do not want to attack the matrix too roughly.

I use a different types of steel dental picks (you can pick up a set on eBay for next to nothing), an one of those sharp craft knives (only very occasionally), a pot of water and a paintbrush. I use the paintbrush to wet the matrix surrounding the fossil (avoiding the fossil as much as you possibly can). I work on one small area at a time, ensuring the matrix in that area is saturated (it soaks up water like a sponge). That turns the matrix into sandy mush which can then be scraped and/or brushed away. Don't work on it dry, because that can produce a lot of dust which you don't want to breathe in, and besides, I think doing it wet is better for the fossil (as long as you don't saturate the fossil as well).

The teeth are always incredibly delicate. I apply a small drop of glue to each tooth, making sure the surface is covered. Then I allow it to dry, before trying to excavate around them. You still have to be very, very careful. Here's a Halisaurus jaw that I 3D prepared using that method. It needs a bit of cleaning up, but it's basically finished.

 

 

Please note that I'm not an expert, others may be able to offer better advice, but that's how I do it. I've also extracted a large prognathodon jaw with the same method.

[LordTrilobite]

Ok. First off, that's a really nice jaw and I see no red flags at all. The bone is genuine and the teeth also look fine. So that's good.

 

It's the front of the lower left jaw, or dentary bone. Roughly half of the bone is missing. I don't think the ID is correct though. This looks more like a Halisaurus jaw. Likely Halisaurus arambourgi as that seems to be the most common species within that genus.

 

 

And this definitely looks like a jaw that would be worth taking out of the matrix as it seems to be in one piece. There wouldn't be any reconstruction work or bone fragments that might not be identifiable. So that's good. But I think you should only attempt a prep like this if you have prior experience with prepping jaws. As Aurelius stated, these small teeth are incredibly fragile. With a lot of patience and the proper technique this is definitely doable. But if you think you don't have enough practice, I think you should probably leave this as is for the time being as it's already quite a nice display piece.

 

 

Definitely a nice pickup though.

[FossilSniper]

56 minutes ago, Aurelius said:

I apply a small drop of glue to each tooth, making sure the surface is covered. Then I allow it to dry, before trying to excavate around them. You still have to be very, very careful. 

Which specific glue did you use on the Halisaurus jaw? That is a very neat piece!
Should I dilute it in some water? Which ratio of glue to water should I use?

 

[LiamL]

I personally love my fossils in the matrix, i think it adds to the story. 

[FossilSniper]

48 minutes ago, LiamL said:

I personally love my fossils in the matrix, i think it adds to the story. 

Everyone is unique 

[snolly50]

Here is my recent prep series concerning jaw sections of this ilk. (I believe yours to be Halisaurus). I hope you will find it helpful.

 

 

I prefer these pieces with some supporting matrix. If you choose to remove the jaw entirely, it would be prudent to consolidate the fossil. Good luck and have fun.

[Tidgy's Dad]

I'd say Halisaurus, a nice piece! 

[Auspex]

3 hours ago, FossilSniper said:

...if there are indeed any problems with it, expert input would not hurt at all.

Please note the absence of vessel foramen in the fossil you are considering.

I believe you have an example of a constructed piece, with genuine mosasaur teeth (not found associated) mated with a carved bone "jaw", and all glued into a composited matrix.

[FossilSniper]

7 minutes ago, Auspex said:

Please note the absence of vessel foramen in the fossil you are considering.

I believe you have an example of a constructed piece, with genuine mosasaur teeth (not found associated) mated with a carved bone "jaw", and all glued into a composited matrix.

Wow.
I did not expect it could just be a piece of bone.
What would a real jaw from the same POV look like?
Is there anything to show that the teeth are glued onto the bone?

Edit: now I see some potential bone marrow on the bottom right-hand edge of the jaw. 

[Auspex]

2 minutes ago, FossilSniper said:

What would a real jaw from the same POV look like?

[FossilSniper]

22 minutes ago, Auspex said:

I think that that is a view from what would have been the outside of the jaw. 
The jaw which is currently in question has its inside view exposed.
The absence of the vessels aren't seen simply because the jaw is upside-down.

I found an example, here it is.
The jaw below is authentic.
To me, the debated jaw may look even more real (due to pressure cracks) than this jaw! \/

Courtesy of @snolly50 for photographing this Halisaurus jaw specimen.

And now the potentially fake jaw:


Remember that this is the bottom-left-front piece of Halisaur jaw. The jaw is very small.
The indentation running through this jaw is what would have been a blood vessel going through the bone.
The indentation in Snolly's jaw is larger simply because his jaw would have been closer to the back, rather than at the front like this one.
Thank you for determining this jaw position @LordTrilobite

[snolly50]

13 hours ago, FossilSniper said:

Courtesy of @snolly50 for photographing this Halisaurus jaw specimen.

My piece shown above is a section of the right dentary, lingual aspect.

 

The original photo stating this thread is a section of left dentary, lingual aspect.

 

The posted view with foramen shows the labial aspect of that piece.

[FossilSniper]

Even if this example is from a different part of jaw, it clearly shows the difference between the inner and outer parts of the jaw.
The top photograph would have been the inside, and the bottom would have been the outside.

I believe that if the jaw is fully exposed, then the vessel foramen will be visible on the alternate side.

[Auspex]

 

Honestly, the bone in this really, really strikes me as off,

from its form and texture, right down to the wipe-on stain.

 

Note that the three distal teeth are unevenly spaced. I think that is an odd morphology, don't you?

[FossilSniper]

33 minutes ago, Auspex said:

Note that the three distal teeth are unevenly spaced. I think that is an odd morphology, don't you?

I agree.

Since this jaw has raised so much controversy, I will simply stay away from it.

It's a solution that always works! 

[FossilSniper]

Again, thank you all for your input.
I value all opinions- after all, this entire forum is based off science!
Unlike other gossiping-based forums, posts are either right or wrong in this forum; and if one is wrong, knowledge is gained! 

[Auspex]

The right one will turn up, and it will be an affordable gem.

[LordTrilobite]

43 minutes ago, Auspex said:

 

Honestly, the bone in this really, really strikes me as off.

from its form and texture, right down to the wipe-on stain.

 

Note that the three distal teeth are unevenly spaced. I think that is an odd morphology, don't you?

I'm sorry but I'm gonna have to strongly disagree. That jaw bone is absolutely definitely real.

There's nothing in that photo that looks in any way fake. True, some of the joins between the teeth and roots are not completely in view, so there would still be a possibility that some teeth are composited on. But based on this photo there's no reason to assume that. The strange spacing is likely due to missing teeth. The teeth all show consistent morphology, which is what we'd expect from a real jaw. Especially the last two teeth show nicely preserved roots that attach nicely to their tooth crowns.

The bone of the jaw itself looks completely normal. The deep furrow running along it is standard for the inside of the jaw. It's called the meckelian groove. The pits are only present on the outside of the jaw. If/when this jaw is prepped out of the matrix, those pits will show eventually on the other side, as we're looking at the inside of the jaw right now. I'd hate for people to think this jaw is suspicious in anyway. Identifying fakes is already hard enough as it is.

 

1 hour ago, FossilSniper said:

Even if this example is from a different part of jaw, it clearly shows the difference between the inner and outer parts of the jaw.
The top photograph would have been the inside, and the bottom would have been the outside.

I believe that if the jaw is fully exposed, then the vessel foramen will be visible on the alternate side.

This is correct. The inside of the jaw is very different from the outside. But this specimen from my collection you're showing here is an upper jaw. So it's a little different.

I have a better example which is a lower jaw. Also a left dentary fragment and also Halisaurus. It's missing the front. But it shows the same deep groove on the inside of the jaw. Nothing out of the ordinary. This feature is completely standard. And as you can see on the lower jaw as well the pits are only present on the outside.

 

[LordTrilobite]

Another even better example of a jaw I recently prepped out of the matrix. Also a left dentary from a type of Halisaurus, but this one is much more complete with the front intact. I only don't have photos after glueing it all back together. So if you're looking for a nice Halisaurus jaw, the one you showed in your post definitely looks like it's worth a buy. Find jaws with nicely preserved teeth are often expensive. Small teeth like these are definitely hard to prep though, due to being so fragile.

[FossilSniper]

27 minutes ago, LordTrilobite said:

But this specimen from my collection you're showing here is an upper jaw.

I'm sorry, I did not realize it was from your collection. 
I should have cited you accordingly.

 

[LordTrilobite]

Oh no problem man. I'm just happy to help with an ID. I mainly meant to clarify that that specimen was an upper jaw, not a lower jaw.

[FossilSniper]

Now that I re-consider my thoughts, I do believe that there were very closely spaced teeth on the jaw, and the fact that some are missing is causing confusion.



I think that this is how the jaw may have once looked.
After all, since the jaw is clearly from a younger individual (It is only 8.9 cm long!), then the teeth would have been more closely placed. 

Here is an example of what I mean by 'closely placed':



This jaw pictured is from the bottom-front-right of a juvenile Halisaurus jaw.
It is basically identical to the one in question, just on the opposite side. Take into account the similar spacing of the teeth and width of the meckelian groove in this jaw.

Thank you for the input! @LordTrilobite

edit: Woohoooooo! 100th post!