Abstract: A device and method for obtaining an identification pattern of polished gemstones. The device comprises, in combination, means for holding the gemstone in a reproducible position, means for creating a collimated parallel light beam, a lens for projecting a pattern obtained by reflecting the collimated parallel light beam from the gemstone onto a plane recording medium facing a plane reference surface of the gemstone. The distinctive pattern may be projected onto the plane recording medium via beam-splitting means. The light used can be white, or monochromatic. Polarized light may be used. Rotation of the pattern about the reference point of the optical axis provides a pattern which may be evaluated automatically.