Gemstone Refractometer,Jewelry Authenticity Tester, Calibration

Professional digital gem refractometer enables oil‑free non‑destructive gem identification. High‑accuracy readings, rechargeable portable design, ideal tool for jewelers, appraisers and gem collectors.Specifications:Product Name: Digital RefractometerMeasuring Range: Refractive index 1.300-3.000;Measuring Error: ±0.005;Measuring Accuracy: 0.001;Display: Backlit LCD screenHouse: Aluminum alloy + ABS switchCalibration blocks: 1.487 & 1.806Battery Life: 10,000 times;Power Supply: 700mA lithium battery;Number of measurements per charge: Approximately 10,000 timesDimensions: 13.5x7.8x2.4cm (5.31x3.1x0.94 inches);Weight: 250 grams (0.55 lbs)Package Contents:1 * Gem Refractometer2 * Calibration blocks (1 * 1.487 mm, 1 * 1.806 mm)1 * Tweezers1 * Tabletop CoverNOTE:For optimal accuracy, always calibrate the device before each use using the included calibration blocks (1.487 mm and 1.806 mm).

• [HIGH‑PRECISION REFRACTIVE INDEX DETECTION]: This gem refractometer adopts total internal reflection principle paired with high‑precision sensor. It covers 1.300‑3.000 refractive index range, with ±0.005 measuring error and 0.001 resolution, delivering non‑destructive accurate optical data for fast gemstone identification.
• [OIL‑FREE TESTING WITH CALIBRATION BLOCKS]: No messy refractive oil required for this digital refractometer. Just lay polished gemstones on the platform to distinguish uniaxial and biaxial crystal structures. Comes with 1.487 & 1.806 calibration blocks for quick pre‑measurement calibration to guarantee reliable test results.
• [BACKLIT LCD SCREEN & LONG‑LASTING TYPE‑C POWER]: Equipped with large backlit LCD display, this gem tester offers legible readings even under dim working conditions. Built‑in 700mAh rechargeable lithium battery supports up to 10000 measurements on one full charge, convenient Type‑C charging for effortless power replenishment.
• [PORTABLE ROBUST CONSTRUCTION]: Compact jewellery testing tool weighs merely 250g. Anti‑corrosion & scratch‑proof aluminum‑alloy outer casing matches insulated ABS switch plus triple insulation protection, bringing stable and safe performance for on‑site mobile detection.
• [BROAD GEM COMPATIBILITY]: Suitable for uniaxial & biaxial gemstones, colored diamonds, moissanite, natural and synthetic gems. Perfect for jewelry stores, appraisal institutes, gem labs, processing factories and personal gem collection evaluation.