Bark Mammoth Ivory

[Shellseeker]

Out hunting today... found lots of interesting stuff, but this thread is about one find.  I have found lots of small pieces of ivory, and a section of Mammoth tusk, and a small Mastodon tusk (I have been lucky but I give my luck lots of hard work and opportunity).

Today I found a large chunk of Ivory and my hunting buddy said it was "Bark Ivory" and they make knife handles out of it, but be careful because it might break...

So this is just a discussion and set of questions when I find something and want more details.  What is Bark Ivory? It does not seem to have Schreger lines.. these lines are straight in one direction.

Does not ALL ivory have Schreger lines?

What is the pock_marked rough exterior?  Is it natural pre-mortem or some sort of boring worms?

If this stuff is fragile, how do I stabilize and/or polish to make those knife handles..

Inquiring minds want to know. and I am thinking that some fossil hunters may have answers.  Thanks.

[Plantguy]

Hey Jack, love the find! 

 

I've wondered about that bark ivory too and never thought to ask anyone...glad you opened this up.

 

My 2 cents..subject to lots of correction... I always thought it was the very exterior of an old individual's tusk showing cementum or possibly the enamel layer if any still existed. It has a decidedly different rough look to it versus the inner layers. Hoping the experts will chime in and correct me. Anyways, I wondering if your specimen has some post mortem holes..maybe borings but I wonder if some gator or other carnivore had some chomping effect too..some of the depressions/holes look similar in size and direction.(wild thought I know and thought I'd throw it out there anyway).... 

 

Here's a photo of a tusk piece (more of an inner section) that i have, maybe 4-5 inches long and you can see that the schreger lines are visible in the thin layers cross section only. Mostly just somewhat parallel lines in the longitudinal section. I think the schregers are present only in the inner dentin layers and you see them in the crosssection/end view. I wouldnt be surprised if you were able to polish the end section of your piece or take a thin section and you'd still see some in some of those inner layers. If you magnify the surface view of the longitudinal section I think you'd see some very distinctive patterning as well. If I run across any of my bark pieces and they are worth showing I'll add em...

Enough of my hypothisizing...Keep throwing these examples out. I enjoy seeing the fragmentary stuff as thats what we usually find! 

Will look forward to more experienced long nosed collectors/experts info. 

Thanks again for the post!

Regards, Chris