It has a light entrance at the back and a built-in filter for the external source of light. A small torch or flashlight (FREE & included in the set), a desktop LED light (optional & not included in the set) and other light source can be use as its source of light when the built-in light source won’t work. This instrument is considered by many to be the most important of all gem testing instruments. It measures the angle at which light traveling through the stone is bent or refracted, called the Refractive Index (RI).
Used this to measure Refractive index of Gemstone or Ore, index of double refraction and identify/authenticate polished precious and semiprecious gemstones as well as observing the optical properties and the structure of gemstones, transparency or opacity and its beauty, durability and scarcity.
Due to chemical composition and crystallization structure, each gem has a typical refractive index. In fact, you can also use this tool to measure R.I. for many minerals in crystal form as long as the crystals have a flat and polished face. Through these parameters, you can determine whether the gem is a Single Refraction (Isotropic) or Double Refraction (Anisotropic or Birefringence) and uniaxial or biaxial photopositive or photonegative.
Features:
- New Design
- 2 in 1 Light Source: Built-in LED Light + External Light Source (flashlight)
- Convenient & easy to carry
- Built-in LED illumination
- FREE Index Fluid and small flashlight/torch
- Built-in Light Source Filter for outside light source
- Approved by strict quality and safety standards
- Undoubtedly durable and very reliable
- Characterized by small volume and less weight
- A popular instrument used on jewelry market
