Birefringence

Birefringence is the strength of double refraction as measured by computing the difference between the high and low indices of a doubly refractive stone. Gems with a high birefringence usually show doubling when observed under magnification.

 

Peridot Ring Exhibiting Doubling Resulting from its High Birefringence.

Peridot Ring Exhibiting Doubling Resulting from its High Birefringence.

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