Sunday, June 22, 2014

Rockabye Fossil.....

 I know, its a weird name for a blog post. But bear with me, you'll understand soon enough...


So if you have been following along, you may already know that I've been working on a 9 million year old rhino jaw in the prep lab at Ashfall that was collected at a private ranch about 10 miles away from the park. Well, it was fairly easy to clean up, and the teeth are still in pretty nice shape. When this side was completely clean, we decided to make a bedding jacket and flip it over so that I can see and clean the other side. It is stable enough that, once the teeth have been reinforced with B-15, I should be able to actually pick it up without plaster supporting it.

I have never made a bedding jacket before. This is something is only done in the lab, and only done with fossils that you want to be able to see both sides of. I have seen them in collections, but to actually remove a jacket from its field jacket is a nerve-wracking, risky endeavor. And to make matters worse, one of the teeth in this jaw had not been properly separated from the plaster when the field jacket was being made. One fossil that another intern was working on earlier this summer had this happen, and as it was small and delicate, it basically exploded when a bedding jacket was made and he tried to remove it from the field jacket. After seeing that, I have been nervously anticipating this day, and applying coat after coat after coat of B-15 to the teeth to try to make sure they would hold.

Now, a bedding jacket is basically a tighter, better made field jacket that, like we mentioned before, is for the purpose of flipping a fossil over. Very. Carefully. Just like with a field jacket, you start with a separator. But unlike with the field jacket, you have to worry about a separator covering two different things. The tin foil in this picture is covering up the fossil to protect it from the plaster. There is also toilet paper on the edges of the jacket covering the plaster that is exposed. The reasoning for these (and for me taking off my ring during the process) is basically this: plaster only likes to stick to three things; more plaster, fossils, and stones.

Once the fossil is protected, we cover the bone with plaster-soaked fabric. We used quilting material instead of burlap because it shapes better and soaked up more plaster. Burlap is better for larger things that require more support. (Back home, instead of quilting material and plaster, we would have used medical bandages called gypsona.)  We let the plaster set over night, and this morning brought the moment of truth.

I was already nervous after watching this fail previously. I've worked hard on this fossil, and I'd really like to see it turn out well. And the less you can move a fossil, the better off the fossil will be. As we were gently loosening it (for some reason it was stuck on something and we weren't able to see what), Rick told me a story about a former intern doing the same thing with a full rhino jaw. She fully covered it and did a beautiful job on the bedding jacket. Then three of them took it and flipped it over, only to have the bedding jacket come away without a fossil in it. When the peaked under the jacket without flipping it back over, they found that it was still securely stuck in the field jacket. Whoops.

Then it came out. There was nothing in the field jacket and everything was intact in the bedding jacket. This side of the fossil still has a little sandstone that needs to be cleaned up next week, but it felt really good to see it in one piece.

Rockabye fossil, on the table top... hey, it has a cradle now! Nice and safe and sound!

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My Story (Very briefly...)

Lots of people claim that they wanted to be paleontologists at the age of 3. So did I. The problem is, I never really grew out of it. My third birthday party had dinosaurs. Everywhere. I grew up digging in fossil dirt from Aurora, NC, looking for coral and shark teeth. I practically lived at my local science museums (and still do, only now I get to do research, fossil preparation, and work in collections!) When local paleontologists discovered a dinosaur with a "fossilized heart" (no longer considered such) when I was little, I got to meet the man who led the work. And then, years later a dinosaur bone with soft tissue turned up. I was officially hooked.
No longer was I dreaming about dinosaurs. I was actively pursuing the science behind prehistoric creatures. I didn't want to read about it, I wanted in on the action. So I started working at the museum, and finally going on my own adventures. And thus, I needed a place to share them and maybe inspire others the way I was inspired. I have gone from watching fossils be prepared from one side of the glass at the museum to working on them on the inside of the glass. I am a student working toward my goal. I can finally start to call myself a paleontologist.