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Color Fading Experiment and Unstable Color Centers


*Fig. A3* Different colors produced by the new treatment (including pink, yellow, orange, and blue) are sorted for this report. Sapphires of different colors are accidentally clustered together by the melting of minerals other than cluster. Note: Different colors are produced in the same heating runs.

*Fig. A4* Natural blue and white Beryllium-Treated sapphires exposed to UV radiation to UV radiation. One half of the piece was kept for reference (left side). Both the blue and white sample developed yellow and orange rims respectively. These rims were found to be the zone of Be-enrichment by LA-ICP-MS (See Fig.A34 and Fig.A45). The color is found to be unstable. The orange rims are fading after exposure to heat.
		*Fig. A5* Polarized UV-VIS-NI absorption spectra of Beryllium-Treated yellow sapphire before and after treatment with UV light. Yellow curve: Spectrum after exposure to UV. Black curve: After fading of yellow sapphire to white color. Note: Shift of the absorption spectrum towards higher absorptions in the blue causes the yellow color in the sapphires in the blue causes the yellow color in the sapphires due to the presence of color centers.

Fig. A6a Fluorescence experiment with Eickhorst UV Lab lamp (long wave 366nm) on faceted sapphires, which had previously been subjected to Beryllium-Treatment. Left: Orangy -pink sapphires (origin: Madagascar) showing intense orangey fluorescence with more yellowish fluoreacence at rim. At right : two samples (origin:Songea) with medium orange-red fluorescence (Faceted gemstones between 2 and 5 cts in size).Note:Yellowish fluorescence is confined to the rim of a Beryllium-Treated orangy-pink sapphire(Fig.A6b)