Naked Science Forum

Non Life Sciences => Geology, Palaeontology & Archaeology => Topic started by: mpmobley on 16/04/2015 16:19:52

Title: What is this rock? What causes the central cavity?
Post by: mpmobley on 16/04/2015 16:19:52
I found this recently in Haleburg, Alabama in a stream while looking for shark teeth (we found 7). I'm an amateur and know little to nothing about geology or paleontology. It doesn't appear to be petrified wood and doesn't look like any of the other rocks around in that area. It feels like rock, has some transparency to it, is hollow, and about 7 inches long. Any ideas? Thanks.
Title: Re: What is this rock? What causes the central cavity?
Post by: mpmobley on 20/04/2015 16:20:26
Here are two additional pictures from the other sides.
Title: Re: What is this rock? What causes the central cavity?
Post by: OokieWonderslug on 30/04/2015 19:17:37
Looks like petrified bark to me.
Title: Re: What is this rock? What causes the central cavity?
Post by: mpmobley on 30/04/2015 19:23:52
I tried the "lick" test on the broken part and it stuck like a sponge.
Title: Re: What is this rock? What causes the central cavity?
Post by: chris on 30/04/2015 20:03:53
What's the lick test?
Title: Re: What is this rock? What causes the central cavity?
Post by: mpmobley on 30/04/2015 21:03:41
I read somewhere that your tongue is much more likely to stick to bone or fossilized bone than rock if you lick it because of the porous nature.
Title: Re: What is this rock? What causes the central cavity?
Post by: mpmobley on 30/04/2015 21:26:35
Here is part of the article that i read...

"Bone vs. Stone: How to Tell the Difference"

By Brian Switek
smithsonian.com
February 3, 2010

"...But let's assume that, regardless of how it was acquired, you have what you think is a piece of fossil bone. Out of its geologic context it is impossible to compare it to the surrounding rock (fossils are often different in color and smoother than rocks from the same deposit), but if there is a break on the specimen you may be able to check its internal structure. A rock or concretion, like the one I showed to my professor, will be solid, and the inside of the rock will look like the outside. Fossil bone, on the other hand, will probably preserve the internal bone structure. In a fossil bone you will be able to see the different canals and webbed structure of the bone, sure signs that the object was of biological origin. You can even try a tongue test. The porous nature of some fossil bones will cause it to slightly stick to your tongue if you lick it, though you might want to have a glass of water handy if you feel compelled to try this."

Title: Re: What is this rock? What causes the central cavity?
Post by: Streets on 20/06/2015 16:40:21
Could be a part of a shark vertebrae.