Polarization imaging for gemstone identification and metrology

This research utilizes polarization raytracing and full-Stokes imaging to investigate the optical properties of four gemstones: cubic zirconia (CZ), natural diamond, CVD synthetic diamond, and moissanite. The study reveals distinct polarization signatures for each gemstone, enabling non-destructive identification and quality assessment.

Cubic zirconia displays symmetric, geometry-driven patterns, while moissanite exhibits extreme linear polarization dictated by its optical axis. Natural and CVD diamonds, despite identical chemical compositions, show differing polarization features, with the natural stones exhibiting more symmetric patterns and a secondary DoLP peak.

The CVD diamonds demonstrate spatially fragmented AoLP and asymmetric DoCP distributions, attributed to stress-induced anomalies in synthetic growth. These polarization differences highlight potential applications in gemstone characterization and could lead to broader uses in distinguishing genuine gems from synthetic alternatives.