There are actually several helpful references online. Here are a few:
http://www.ehow.com/how_5956138_do-bracelet-made-out-jet_.html 
http://www.jmfelton.com/jetid2.htm 
http://www.blackasjet.co.uk/acatalog/whitby_jet.html 

Daniel B. Davis
Archaeologist Coordinator
Kentucky Transportation Cabinet
Division of Environmental Analysis
200 Mero Street
Frankfort, KY 40622
(502) 564-7250

-----Original Message-----
From: HISTORICAL ARCHAEOLOGY [mailto:[log in to unmask]] On Behalf Of
Gerda Coetzee
Sent: Tuesday, May 10, 2011 8:53 AM
To: [log in to unmask]
Subject: Help with black buttons please

Good day,

I'm sending the following request on behalf of myself and a colleague,
who is helping me with the identification of buttons found at a
farmstead site, dating approximately 
between the 1880s and the 1920s:

Could you please advise me on how to distinguish between jet, black
glass, and bakelite buttons. How can I make a positive identification? 

Thank you very much.


Gerda Coetzee
Department of Archaeology 
National Museum 
P.O. Box 266
Bloemfontein
9300
South Africa
Tel.. 051-447 9609
Fax  051-447 8043
Sell  083 658 7875
Email:  [log in to unmask]

National Museum website:  www.nasmus.co.za


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