FGR-003A gem refractometer Technical Parameters: 1, cubic zirconia (CZ test prism), 2, the measurement range: 1.35 - 1.85, 3, accuracy: ≤ ± 0.003; professional optical design, the shadow boundary is super straight and clear; 4, large eyepiece, high magnification, wide field of view; 5, all stainless steel countertops, corrosion-resistant, easy to clean; built-in quasi-monochromatic LED light source; 6, the unique dual power supply: two 7-cell batteries or an external DC3V DC power supply, equipped with 2ml refractive oil and a polarizer; 7, unique refraction oil bottle design (patented technology ZL200620096730.7), overcome the defects of traditional oil bottles such as fragile, easy to spill, poor control of drop volume, safer, more economical and more convenient to use; metal instrument box, Exquisite appearance; 8, two-level dimming, easy to measure the refractive index of gemstones of different nature. Instructions: 1. Approximate method (mainly for faceted gemstones, requires a well-polished enough plane) 2, (1) cleaning gemstones and refractometers (eyepieces, prism tables) 3, (2) open the light source, observe the clarity of the field of view 4. (3) Select the largest facet of the gemstone and place it on the metal table. 5. (4) Lightly contact the liquid in the center of the prism, usually 2mm in diameter (and record the RI of the contact liquid) 6, (5) gently push the gem to the center and make it good contact 7, (6) cover, myopia readings (high and low values, need to estimate three decimal places) 8, (7) turn the direction of the gemstone, repeat the test (record the highest and lowest values) 9, (8) launch gems, clean gems and prisms 2, far vision method (also known as point measurement method) Note: (1) Polished curved gemstones and faceted gemstones (2) Only the measurement of myopic refractive index (two decimal places) Steps: (1) Cleaning the gemstones and prisms (2) Put a drop of oil on the metal table (3) Holding the gemstone, contact the oil droplet on the metal table with a curved surface to make it stain (4) Place the gemstone in the center of the prism (as long as the axis is parallel to the long axis) (5) The eye is 30~45cm away from the eyepiece, and the head reading is moved (the half-dark position of the droplet image is the refractive index of myopia)
Instructions: 1. Approximate method (mainly for faceted gemstones, requires a well-polished enough plane) 2, (1) cleaning gemstones and refractometers (eyepieces, prism tables) 3, (2) open the light source, observe the clarity of the field of view 4. (3) Select the largest facet of the gemstone and place it on the metal table. 5. (4) Lightly contact the liquid in the center of the prism, usually 2mm in diameter (and record the RI of the contact liquid) 6, (5) gently push the gem to the center and make it good contact 7, (6) cover, myopia readings (high and low values, need to estimate three decimal places) 8, (7) turn the direction of the gemstone, repeat the test (record the highest and lowest values)
