gemological refractometer gemstone testing instrument

FGR-003 Gemological Refractometer The refractometer is considered by some to be the most important of all gem identification instruments. It can be indicated (not measures) the refraction index of a gemstone, which often gives vital clues to the identity......

...Testing Instruments Refractometer with Testing range 1.35-1.85 The refractometer is one of the most important tools in a gemological laboratory. It indicates the refraction index of a gemstone, which often gives vital clues to the identity of a gemstone. Refractometer Fable brand with. Many gemstones are double refraction(birefringence) on optical character. For the gemstones,you must test......