Refractometer for Gem Testing
Hard Cube Zirconia measuring prism.
Scale range:1.35-1.85.Accuracy: ±0.003,
High quality optical scratch proof glass.
Aluminum alloy table which is 45mm thick.
By advanced optic system,shadow edge is straight and sharp,easy to read it.
Internally installed the narrow band witch (monochromatic) light.
There are two ways of inputing the voltage: AAbatteries and DC3V direct current supply(AC100—240V).
National patent designed oil bottle. The bottle has a unique design (Proprietary technology ZL200620096730.7),It is much safer ,much ecnomical and more convinent.
3.AA battery x2
4.AC100-240V power suppy
5.refractive index Liquid(1.78±0.005)with unique designed bottle
6.Refractometer Index Reference List (up to 200 common gemstones, i.e. Calcite, Jadeite, Quartz etc.)
8.Suitcase with key
Open the upper cover then wash the gem and prism with alcohol.
Lay the instrument on the worktable. Drop a little bit of special refractive oil onto the surface of prism and press it by a thin glass bar. (Be sure not too much or too little)
Make sure the ground surface of gem to be measured is close to the prism, press it again lightly, let the refractive oil be evenly distributed between the two surfaces then close the upper cover.
Press the light momentary switch, make sure that the internal light source is turned on when testing.
Move the eyepiece up and down and adjust the diopter accordingly. By this time you can see a light/dark boundary in the viewing field. The gradation (shade) on which the boundary located is called the refractive index of gem.
Remove the polarizer. Turn it onto eyepiece. Then turn the polarizer lightly. You can only read the refractive index value in one direction at a time because the polarizer only allows the light vibrated in one direction to pass through.
Turn the polarizer through 90°, you can measure the refractive index value of the light vibrated at right angles to that mentioned above.
Turn the gem in the same direction through small degree then turn the polarizer lightly according to above method, you can read the two refractive index values of the light vibrated at right angles to each other.
Operate continuously until the gem is at 180° position to its initial position. From a number of groups of measured refractive index values you can find the maximum and minimum refractive index. The difference between the two values is the birefringence of gem.
After measurement, remove any dirt from the refractometer's housing (casing) then clean the prism and the gem with alcohol to remove the refractive oil on it.
Put back the refractometer into the box for protection.
Remove the Battery from the Battery compartment if you are planning on not using the Refractometer for a long period of time to prevent leaks or molds that can damage your device.
Thanks for your visit our website
If have any question,pls to contact us