Digital Gemstone Refractometer, Professional Jewelry Tester with High-Precision Sensor, Refractive Index 1.300-3.000, No Refractive Oil Needed for Jade Crystal Diamond

As a core tool in the field of jewelry identification, it can measure the refractive index of gemstones non-destructively, quickly and with high precision.It is widely used in jewelry appraisal institutions, gem processing factories, collectors and other scenarios.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). 3.The bright backlit LCD display ensures clear readings anywhere.4. Insulation Switch: Made of ABS material.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:1 * Gemstone Refractometer2 * calibration Block (1*1.487,1*1.806)1 * Aluminum Box1 * Tweezers1 * Countertop cover1 * Instruction ManualNotes：For optimal accuracy, always calibrate the device using the included calibration blocks (1.487 & 1.806) before each use session.

• 【Precise Measurement】:This refractometer built-in high-precision sensor covers a measurement range of 1.300-3.000, meeting the identification needs of most common gemstones and providing quantitative data to support identification results. The measurement error is as low as ±0.005.
• 【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.
• 【Easy to Use】No need to use refractive oil, just bring the sample close to the measuring platform to measure. Based on this parameter, you can tell whether the gemstone is uniaxial or biaxial. In addition, it is equipped with two calibration blocks of 1.487 and 1.806, which need to be calibrated before measurement to ensure the accuracy of the measurement results.
• 【Excellent Design】The portable design makes the jewelry refractometer compact and lightweight, weighing only 250 g. And it adopts hard aluminum alloy to create a work surfaces, which is scratch-resistant and sturdy, providing stable support for precision testing. In addition, it is equipped with an LCD backlit display and ABS insulated switches, with built-in triple insulation protection, ensuring clear and bright viewing comfort while ensuring safe use.
• 【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.