Turtle Shell

[IonRocks]

This is at the Denver show, but I don't know enough about turtle shells to purchase it. It is very low priced which worries me

[Darktooth]

I am by no means an expert but that does not look like any turtle shell that I have seen. Where is it supposed to be from and what is the age?

[IonRocks]

Oligocene, White River I believ

[Darktooth]

And could you take close-ups of specimen so we can see texture better? 

[IonRocks]

I'd rather not appear too interested in it. The texture seems fairly normal for turtle shell.

[JohnBrewer]

I know @MarcoSr has found turtles, he might be able to help. 

[Troodon]

Pretty weathered but looks real.

 

[IonRocks]

I went ahead and purchased it. Driving home. Will take more photos in an hour or so.

it came with more shell pieces that had fallen off. I only paid $40 so in the end, wether or not it's real it's worth it

its fairly large compared to other shells I've seen, somewhere between 8-12"

[JohnBrewer]

Wow, $40! Fingers crossed for you. 

[IonRocks]

Some side views

[JohnBrewer]

In my opinion with finding turtle shell fragments/scutes from the Isle of Wight the side view says to me it's real! 

[IonRocks]

And here is a broken area on it.

 

So another question I have then, is how would one go about re assembling a turtle shell. I have quite a lot of shell in a bag from it.

[jpc]

It looks like a real South Dakota White River turtle to me.. incpomplete , yes, real, yes.  Difficult to remove that red stuff, so maybe just leave it like that. 

[IonRocks]

So I do have a lot of extra shell, any advice for how to make use of it? 

[Troodon]

15 minutes ago, IonRocks said:

And here is a broken area on it.

 

So another question I have then, is how would one go about re assembling a turtle shell. I have quite a lot of shell in a bag from it.

 

It's a jigsaw puzzle.  Takes time and start by laying out all of pieces and gluing as you find mating pieces.  Clean as you go.

[IonRocks]

Does anyone have any reccomendations on glue/epoxy to use? I'm working with quite a bit of gap between the rock and the shell, so I am thinking epoxy. I haven't used much other than household glues before, but I don't think those will suffice with this.

[LordTrilobite]

Looks like a really fun puzzle. Really nice piece and definitely real.

 

Some tips on putting it back together. One of the most important things is that the broken areas are clean so they can fit back together nicely. Depending on if the bone is really fragile or not, you might have to stabilise the pieces before you put them back together without without touching the broken faces. What you can do to prevent them from breaking any further is using Paraloid B-72. This glue disolves in acetone so it can be removed if you make a mistake. It's good for stabilisation, less so for repair. What you can do is use the B-72 on the outside surface of each piece, just on one side to stabilise it a bit. Becareful not to get the B-72 on the broken surface.

 

So now the pieces are stable and wont break apart so easily anymore you can start puzzling. There's no easy way to do this, you'll just have to try a lot of pieces on each other see if they fit. In these sort of tasks I always sort all the pieces by size as well as colour. Sometimes the colour can be a great help as the subtle varation in fossils can help you see what is from what area. Though this piece seems to be mostly the same colour. And then just pick up one piece, and start putting it up against all other pieces. The best way to know if it fits is by feeling it. skip the sides that you know dont have to be glue on to something (the top and bottom of the shell). Once you've tried all notable pieces on this piece. Lay it aside in a separate catagory to note that you've already tried this piece. Then pick the next piece and repeat the process. I find that starting with the pieces that have a weird shape helps a lot. Wierd shapes are sometimes easier to fit visualy to other pieces.

 

Once you find two pieces that fit. I suggest you don't use Paraloid B-72. But instead use Cyanoacrylate, which is just super glue. You need the type that's thin like water so that it gets in all the cracks. The advantage is that it cures fast and helps to glue pieces together quickly. The downside is that it's really not reversable. So make absolutely sure the two pieces match perfectly before you glue them.

 

I hope this helps. And good luck!

[Troodon]

I would purchase a small bottle of paleobond, red bottle and use it to attach your pieces.  You can always use acetone to reverse the process if there is a mistake.   Again, like I and others have noted make sure your pieces are clean before attaching.  I would leave the larger cracks alone and just focus on your puzzle.  I like to try fitting the loose pieces together first to each other then to the shell.   You may also not have all the pieces and will have gaps in the shell.  

http://www.paleobond.com/

If you live close to Denver I think the paleobond folks are at the show

[IonRocks]

Well, all the pieces are stable, some have cracks but it looks like a good amount of prep had already been done. A large crack through the entire tortoise was glued/stabelized. Some other pieces of shell were affected by that, and are in a bit of a weird position. So I have pieces that are just slightly offset, but enough that I can't seem to fit some matching pieces into the holes they belong in.

 

[Darktooth]

Well like I said earlier I'm not an expert. I am glad I was wrong. And I am glad you got what you wanted. Cant wait to see it finished!

[JohnBrewer]

I'd use 10%/90% w/v Paraloid B-72 and acetone to stabilise and 35%/65% w/v Paraloid B-72 and acetone as an adhesive. At this strength it glues perfectly well and is reversible. If the edges to be glued are soft and crumbling a little use the first stabilising solution before using the adhesive. This allows the initial  Paraloid to soak in and give the adhesive mix something solid to grab onto. 

[JohnBrewer]

6 hours ago, IonRocks said:

Well, all the pieces are stable, some have cracks but it looks like a good amount of prep had already been done. A large crack through the entire tortoise was glued/stabelized. Some other pieces of shell were affected by that, and are in a bit of a weird position. So I have pieces that are just slightly offset, but enough that I can't seem to fit some matching pieces into the holes they belong in.

 

 

Oops missed this before I wrote my first post! If some of the repaired parts are a bit wonky you might be able to free them with acetone and reglue providing an archival/reversible adhesive was used. Good luck, looks like a fun project.