Colour:B Features:1.All kinds of gems can be determined according to the index of refractive index, because different gemstones have fixed refractive index.2.This parameter can be used to determine whether a gem is a uniaxial crystal or a biaxial crystal.3.Unique design, extremely low power consumption and easy to carry.4.High quality and high accuracy measurement results.5.Through strict quality and safety standard test, long-term service life. Product specifications:1.Measurement range: 1.30 ~ 1.81RI.2.Minimum dividing value: 0.01RI.3.Size: about 30x70x130mm.Included:Style A:1 x Refractometer1 x FlashlightStyle B:1 x Refractometer1 x Refracting oil
