Digital Jewelry Tester, High Precision Gem Refractometer with 0.001 Accuracy, Compact Lightweight Structure for Lab Jewelry Store & Gemstone Identification

Gemstone refractometer uses precise measurements of the refractive index—an undeniable physical metric—to instantly determine the authenticity of a diamond, allowing professionals to see for themselves.Advantages：1. Skip the messy refractive oils! Simply place your gem or solid sample onto the measurement platform for a fast, clean, and contactless reading.2.Crafted from lightweight yet rugged high-strength aluminum alloy (only 250g / 0.55 lbs). The bright backlit LCD display ensures clear readings anywhere.Specifications：Size: 135 x 78 x 24 mm (5.31" x 3.07" x 0.94")Weight: 250g (0.55 lbs)Measurement Range: Refractive Index 1.300 ~ 3.000Accuracy: ±0.001Measurement Error: ±0.005Battery Capacity: 700mAh BatteryApprox. Measurements per Charge: ~200What’s Included:Gemstone Refractometer × 1Protective Case × 1User Manual × 1Notes：For optimal accuracy, always calibrate the device using the included calibration blocks (1.487 & 1.806) before each use session.

• 【Easy Testing】No refractive oil is required, just bring the sample's measuring surfaces close to the measuring platform of digital refractometer to measure. Based on this parameter, you can determine whether the gem is a uniaxial crystal or a biaxial crystal.
• 【Professional Identification Tool】:This refractometer provides accurate refractive index measurements ranging from 1.300 to 3.000, with an exceptional accuracy of ±0.005 and resolution of 0.001.
• 【High Quality Materials】: The gem refractometer uses hard aluminum alloy to create a work surfaces, which is scratch-resistant and sturdy, providing stable support for precision testing. It is equipped with an ABS engineering plastic power switch and built-in triple insulation protection to effectively block the risk of leakage.
• 【Wide Range of Applications】: This digital refractometer can quickly and accurately identify single and double gemstones, diamond colored gemstones, designed for measuring the refractive index of gemstones and solid materials.
• 【Working Principle】: The working principle of the refractometer is based on total internal reflection. The refractive index is a very important optical parameter,this key characteristic allows users to accurately identify and differentiate gem types based on their unique optical properties.