BS E-line Gemological Refractometer 44-861

- Low cost, lightweight instrument using refractive index to identify and authenticate polished precious and semi-precious gemstones in jewellery and gemstone industries 
- Can also be used to identify whether a particular precious stone is Isotropic or Anistropic (uniaxial or biaxial)
- Supplied with hard carry case, polariser, illuminator (torch) and instructions including summary of typical refractive index values