The alexandrite effect

This is an unusual case of pleochroism (color change) in stones, depending on the properties of the external flow of light.
This anomaly can be manifested in both natural and synthetic samples and not only directly in alexandrite, but, for example, in corundum.
Quite often customers bring us items of the postwar period with large panels that changes color with natural and artificial light, with full confidence that in their hands they hold the alexandrite. However, according to the results of diagnostic studies in 90% of cases it is synthetic corundum with alexandrite effect.
It is worth Recalling that alexandrite and corundum are completely different mineral varieties, and the presence of corundum color change effect does not EQUATE it to alexandrite!

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