【JEWELRY IDENTIFICATION TOOL】: Gemstone identification instruments Composed of a high-sensitivity sensor and LCD screen, this tool enables non-destructive, rapid, and accurate measurement of gemstone refractive index, determining other optical properties. Refractive index range: 1.300-3.000, measurement accuracy up to 0.001, measurement error: ±0.005 【CLEAR VISUAL READING】: Digital gemstone refractometer For Jewelry Equipped with a large backlit LCD screen, high-sensitivity sensor, and intelligent electronics, ensuring clear readings even in low-light conditions. Each charge supports up to 10,000 measurements, suitable for various applications including laboratory, field gem identification, and jewelry stores 【TESTING METHOD】: Portable Gem Refractometer Jewelry No refractive oil required; simply place the sample measurement close to the measuring platform. Based on this parameter, you can determine whether the gemstone is a uniaxial or biaxial crystal. Two calibration blocks with refractive indices of 1.487 and 1.806 are also included, calibrated before measurement to ensure accuracy 【OPTICAL MEASUREMENT PRINCIPLE】: Diamond Tester Professional Utilizing the principle of total internal reflection, the critical refractive index of a gemstone is determined. This is a fundamental optical property for accurately identifying and characterizing gemstones, providing a scientific basis. Its compact and lightweight design ensures easy portability. The aluminum alloy casing extends its lifespan 【COMPATIBLE WITH MULTIPLE GEMSTONES】: Gemstone Measuring Instrument Capable of quickly and accurately identifying single-crystal and twinned gemstones, including moissanite, diamonds, colored gemstones, natural or synthetic gemstones, minerals, and other solid materials. Specifically designed for measuring the refractive index of gemstones and solid materials