This high-precision refractometer is designed for reliable and accurate measurement of the refractive index (RI) of gemstones and transparent materials. Built for gemologists, jewellery professionals, and laboratories, it provides essential data for gemstone identification and material analysis Key Features Precision Optical SystemOffers a clear, stable RI scale typically ranging from 1.30–1.81, suitable for most gemstones Durable Testing PlateHigh-quality optical glass test plate ensures excellent contact with gemstones and long-term durability. Option With or Without Built-In Light Source Without light source: For use with an external monochromatic light With light source: Integrated LED illumination provides uniform lighting and easy readings in any environment Fast, Easy ReadingsSimply place the polished surface of a gemstone on the test plate with contact liquid and view the RI boundary line through the eyepiece Essential for Gem IdentificationRefractive index is one of the most important optical properties used to distinguish gemstones and detect imitations Applications Gemstone identification Distinguishing natural stones, synthetics, and simulants Laboratory testing Jewellery workshops and appraisal offices This refractometer provides dependable, professional-grade performance for anyone requiring accurate refractive index measurement, a must-have tool for every gemologist or jewellery specialist