This item is commonly known as Gemstone Refractometer, is the primary and most powerful tool in identifying and authenticating polished precious and semiprecious gemstones and also observing the optical properties and the structure of gemstones. This model is just as good as the expensive models used in gemological institutes, it has a built-in light source and with the aid of the Contact liquid (RI Fluid), which creates an optical contact between the glass and the gemstone, you can measure or test the Refractive Index of faceted stones, its transparency or opacity, and its beauty, durability and scarcity.
