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 Post subject: Elephant ivory vs mammoth
PostPosted: Fri Mar 13, 2015 9:31 am 
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We are aware of the continuing effort to stop the importation and trade of elephant ivory. Some are trying to make positive differentiation. Walrus ivory is easier to tell apart.

I am looking for those familiar with any experience regarding mammoth ivory. How to tell apart? Has anyone done tests on the differences of these two?


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 Post subject: Re: Elephant ivory vs mammoth
PostPosted: Fri Mar 13, 2015 2:42 pm 
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Carbon dating! ;)

I guess part of the question is, what non-destructive indicators, and how do you convince a skeptical customs agent that you're not dealing in contraband?

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 Post subject: Re: Elephant ivory vs mammoth
PostPosted: Fri Mar 13, 2015 3:54 pm 
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They have different patterning iirc, and because of that it's not hard for an expert to differentiate them. I have heard of agents buying samples to test, though customs people can often be less discerning.

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 Post subject: Re: Elephant ivory vs mammoth
PostPosted: Fri Mar 13, 2015 5:52 pm 
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May I recommand this very good book of Maggie Campbell Petersen, which will help you :
http://www.maggiecp.co.uk/book.html

In mammoth ivory the crisscross design of Schreger lines form angles under 90 degrees ; in elephant ivory these angles are above 90 degrees.

You can find plenty of information on internet about this.

Check as well this link, page 10 :
http://www.cites.org/eng/resources/pub/ ... -guide.pdf


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 Post subject: Re: Elephant ivory vs mammoth
PostPosted: Sat Mar 14, 2015 2:48 pm 
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Thanks Isi. Yes, I have enlisted the aid of Maggie in this. Your suggestions are right in line with my search for answers. There was some great information found in the links. Carbon dating would be a good one too, but not a readily accessible instrument. Anyone know of additional gemmological instruments like XRF, FTIR, Raman, etc. that would be of aid?

I really liked this bit from the CITES link: "Another feature may be used to identify mammoth ivory. Mammoth ivory will occasionally display intrusive brownish or blue-green colored blemishes caused by an iron phosphate called vivianite. Elephant ivory will not display intrusive vivianite discoloration in its natural state. It is of interest to note that when the discoloration is barely perceptible to the eye, the use of a hand-held ultraviolet light source causes the blemished area to stand out with a dramatic purple velvet-like appearance. Even if discolored, elephant ivory will not have the characteristic fluorescence of vivianite."


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 Post subject: Re: Elephant ivory vs mammoth
PostPosted: Sun Mar 15, 2015 2:21 pm 
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Hi Mr. Williams!

I am not familiar wit ivory and mammoth at all, but what I can do for you, I can tell my guy to get a few samples of mammoth-bone at the mineral show in Chelyabinsk on the coming weekend and send to me. Then I will just forward samples to you for you own research. Actual bones are from "mammoth graveyard" near Tobolsk in Siberia.

Samples will not be large as he will need to fit in standard bubble-envelope.. :)

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 Post subject: Re: Elephant ivory vs mammoth
PostPosted: Mon Mar 16, 2015 2:49 pm 
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Hi,
It is pretty simple with FTIR: bone and tuck basically is made of Hydroxyapatite (HAP) with collagen (Amide I, II, III). After few tenth of a year bone starts to lose water, after thousands year collagen starts to decomposite: so there is distinctive difference between FTIR spectra of mammoth and elephant tusk additionally it is possible to make difference to different type of cut bones (from tusk). Sampling: I use DRIFT with sampling sticks, nondestructive and fast...
Peters


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 Post subject: Re: Elephant ivory vs mammoth
PostPosted: Mon Mar 16, 2015 2:53 pm 
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small addition: you could use GemmoFTIR with PE sampling stick by Mikko and it could be easy to add it to preconfigured aplication.


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