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Zwaan, J. H. (2020). Colour-Change Garnet from Tanga, Tanzania. The Journal of Gemmology, 37(2), 133-134.
Krzemnicki, M. S., Hanni, H., & Reusser, E. (2001). Colour change garnets from Madagascar: Comparison of colorimetric with chemical data. Journal of Gemmology, 27(7).
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Bisserl was zum Lesen (findet sich im Netz) ;-)
Gruß, Martin