Refractive index is one of most important optical parameter. Gloss of gem can be estimated by the parameter.
The kinds of gem can be precisely determined in accordance with the measured value of refractive index because every kind of gem has its inherent refractive. Besides, index of double refraction can be also measured. Through the parameter you can judge whether a gem is uniaxial or biaxial photopositive or photonegative.
The gemological refractometer is characterized by small volume and less weight. It is easy to carry. It is a popular instrument used in jewelery market.

Model: RHG-181
Range: Refractive Index: 1.30-1.81
Min. Div. : Refractive Index: 0.01