Based on this parameter, you can determine whether the gem is a uniaxial crystal or a biaxial crystal.In addition, it is equipped with two calibration blocks of 1.487 and 1.806, which are calibrated before measurement to that the measurement results are accurate. The gem refractometer uses hard aluminum alloy to create a work surfaces, which is scratch- and sturdy, providing stable support for testing. It is equipped with an ABS engineering plastic power switch and built-in triple insulation protection to effectively block the risk of leakage. The data gemstone refractometer is composed of high-sensitivity sensors and LCD screens.It can measure the refractive index value of gemstones non-destructively, quickly and accurately, and can determine other optical characteristics of gemstones. Jewelry Tester Identification Tool featuring a large LCD screen with backlight illumination, a high-sensitivity sensor, and intelligent electronics, the device ensures excellent readability even in low-light conditions. Powered by a rechargeable 700mAh lithium battery Gemstone ldentification Tester Suitable for both uniaxial and biaxial crystals, this jewelry calibration test tools quickly and accurately identifies single and double gemstones-including moissanite, , colored gems, natural or synthetic stones, minerals, and other solid materials., Weight: 1.52559885304 pounds, Manufacturer: Taviko