Each gem has a typical refractive index due to its chemical composition and crystallization structure. The gem refractometer can observe the optical properties and the structure of a gemstone. Through the parameters you can judge whether the gem is an anisotropic stone or isotropic stone. The stone needs a flat and polished facet. Contact liquid(RI Fluid) is also needed when testing. 1. Open the upper cover①. Wash the gem and prism⑤ with alcohol. 2. Lay the instrument on the worktable. Drop a little bit of special refractive oil onto the surface of prism⑤ by a thin glass bar. (Be sure not too much or too little) 3. Make the ground surface of gem to be measured close up to the prism⑤, depress it lightly, make refractive oil distributed evenly between the two surface. Then close the upper cover①. 4. Press the Led momentary switch② to make sure the internal light source is on when testing. 5. Move eyepiece④ up and down. Adjust diopter approximately. Now you can see a light/dark boundary in the viewing field. The graduation on which the boundary located is the refractive index of gem.
P**Y
Refractometer
This thing works OK but I found that it works on cut stones and sucks for uncut stones. If you have an absolutely smooth crystal face, it works but if its a rough surface, not so good. The shadow is a bit hard to find and most minerals read a tiny bit low. Something that should read at 1.55 will usually read about 1.52 or 1.53. If you want to read a Diamond, you can forget it because diamond is above 2 and the scale stops at 1.8. I'm glad I bought it because I've always wanted one but they were too expensive. This one is within my budget.
S**L
Three Stars
Did not come with RI fluid
A**R
Five Stars
Fast delivery came with ri fluid
Trustpilot
2 weeks ago
2 months ago
