GemologyOnline.com
https://www.gemologyonline.com/Forum/phpBB2/

Trace Element characterization of tourmalines worldwide
https://www.gemologyonline.com/Forum/phpBB2/viewtopic.php?f=13&t=21518
Page 1 of 1

Author:  Jason Barrett [ Sat Jul 18, 2015 2:02 am ]
Post subject:  Trace Element characterization of tourmalines worldwide

Okay....I got this reference material and findings from Al Falster at UNO. I have him send me write-up's and reports/powerpoints they use for their graduate class. This is data collected by Al, Karen Webber, and Skip Simmons. They are trying to create a database of known pegmatite tourmaline deposits from around the world. By collecting and sampling tourmalines they will be able to ID a specific location a tourmaline has come from.

Trace Element Characterization of Tourmaline from World-wide Pegmatite Locations


Color-causing elements in tourmaline

Pink and red
-Mn3+ content, also Mn2+/Mn3+ IVCT
-Color center electron trap in vacant anion position

Yellow and brown
-Ti4+/Mn2+ IVCT
-Fe3+ or Mn2+ content
-Ti4+/Ti3+ IVCT
-Hole traps of type O- in interaction with 2 Al nuclei caused by irradiation

Green, blue and black
-Fe2+ contents
-Fe2+/Fe3+ IVCT (black in high concentrations)
-V3+ or Cr3+ contents

Here are some of the samples they tested. Some of these were collected at the actual locations, if I am not mistaken. I know they have been to Mauvco and Batalha before
Attachment:
Mozam paraiba_opt.jpg
Mozam paraiba_opt.jpg [ 18.5 KiB | Viewed 2573 times ]

Attachment:
nigeria paraiba_opt.jpg
nigeria paraiba_opt.jpg [ 15.83 KiB | Viewed 2573 times ]


Attachments:
tourmaline 1_opt.jpg
tourmaline 1_opt.jpg [ 18.94 KiB | Viewed 2573 times ]

Author:  Jason Barrett [ Sat Jul 18, 2015 2:06 am ]
Post subject:  Re: Trace Element characterization of tourmalines worldwide

Attachment:
tourmaline 2_opt.jpg
tourmaline 2_opt.jpg [ 15.46 KiB | Viewed 2572 times ]

Attachment:
tourmaline 3_opt.jpg
tourmaline 3_opt.jpg [ 25.5 KiB | Viewed 2572 times ]

Here are a bunch of dissolved tourmaline samples, diluted to 35ml
Attachment:
tourmaline samples_opt.jpg
tourmaline samples_opt.jpg [ 23.01 KiB | Viewed 2572 times ]

Author:  Jason Barrett [ Sat Jul 18, 2015 2:20 am ]
Post subject:  Re: Trace Element characterization of tourmalines worldwide

Here are some pretty decent looking samples of tourmalines from different locations like Namibia, Brazil, and Afghanistan. This picture was taken right before these crystals got fused and dissolved..... :shock:
Attachment:
Picture7_opt.jpg
Picture7_opt.jpg [ 16.88 KiB | Viewed 2571 times ]

Attachment:
Picture1_opt.png
Picture1_opt.png [ 16.52 KiB | Viewed 2571 times ]


PINK TOURMALINE
Attachment:
Picture2_opt.png
Picture2_opt.png [ 20.52 KiB | Viewed 2571 times ]

Author:  Jason Barrett [ Sat Jul 18, 2015 2:22 am ]
Post subject:  Re: Trace Element characterization of tourmalines worldwide

GREEN TOURMALINE
Attachment:
Picture3_opt.png
Picture3_opt.png [ 22.9 KiB | Viewed 2571 times ]

Attachment:
Picture4_opt.png
Picture4_opt.png [ 15.55 KiB | Viewed 2571 times ]

Attachment:
Picture5_opt.png
Picture5_opt.png [ 13.56 KiB | Viewed 2571 times ]

Author:  Bear Williams- SGL [ Mon Dec 12, 2016 5:19 pm ]
Post subject:  Re: Trace Element characterization of tourmalines worldwide

Fascinating. Thanks for this Jason.
Will there be a paper from you and Al?
Bear

Author:  Barbra Voltaire, FGG [ Mon Dec 12, 2016 7:35 pm ]
Post subject:  Re: Trace Element characterization of tourmalines worldwide

Thanks Jason. Excellent!

Author:  Tom Herman [ Fri Dec 16, 2016 1:13 am ]
Post subject:  Re: Trace Element characterization of tourmalines worldwide

Jason,

Excellent work! And thanks for including the various Maine Tourmalines... It's good to see that those classic locations are being studied and not forgotten.
I never got to Dunton or Newry, but did go through Mount Mica and was able to pick up a few small Rubellite fragments.

-Tom

Page 1 of 1 All times are UTC - 4 hours
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
http://www.phpbb.com/