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Chromium-bearing Elbaite from
Umba River (Umba Valley), Korogwe Rural District, Tanga Region, Tanzania


00942920017271929495621.jpg
Chromium-bearing Elbaite

Umba River, Korogwe Rural District, Tanga Region, Tanzania
03618050017369951982151.jpg
Chromium-bearing Elbaite

Umba River, Korogwe Rural District, Tanga Region, Tanzania
00942920017271929495621.jpg
Chromium-bearing Elbaite

Umba River, Korogwe Rural District, Tanga Region, Tanzania
02709420017271929487289.jpg
Chromium-bearing Elbaite

Umba River, Korogwe Rural District, Tanga Region, Tanzania
00942920017271929495621.jpg
Chromium-bearing Elbaite

Umba River, Korogwe Rural District, Tanga Region, Tanzania
02709420017271929487289.jpg
Chromium-bearing Elbaite

Umba River, Korogwe Rural District, Tanga Region, Tanzania
Locality type:River
Classification
Species:Elbaite var: Chromium-bearing Elbaite
Formula:Na(Li1.5Al1.5)(Al,Cr)6(Si6O18)(BO3)3(OH)3(OH)
Comments:Shows the so called Usambara effect, with hue changing from green to red with increases in path length of light through the material.
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Chromium-bearing Elbaite data
Locality Data:Click here to view Umba River (Umba Valley), Korogwe Rural District, Tanga Region, Tanzania
Photo GalleryView Gallery (2 photos)
Data Identifiers
Mindat Occurrence Record ID:47595
Long-form Identifier:1:3:47595:8
GUID (UUID V4):0
References
Journal of Gemmology 1999, Volume 26 No. 6, 386-96
 
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