Polariscope, buy Desktop Gem Polariscope Optical Instrument on China Suppliers Mobile

Product Details

Specifications

Desktop Gem Polariscope optical instrument
With rotatable sample platform.
CE certificate

Desktop Gem Polariscope

Polariscope Description:

Shows if a stone is doubly or singly refractive through a pair of polarized lenses encased in a sturdy plastic frame. Includes LED light source that attaches beneath the polariscope and protective carrying case.

1. Polariscope with 49mm heavy calibre.

2. With rotatable sample platform.

3. With white long life LED cold light source.

4. Accompany with a AC adapter, the power supply can also be two AAA type batteries

Option one: LED light source

Option two: halogen lamp

Interference Ball

Table Top Polariscope Instructions
A polariscope is used to differentiate between singly (isotropic) and doubly refractive (anisotropic) stones. A stone is placed between two polarizing filters and the top filter is then turned. If used with a conoscope, interference figures can also be seen with a polariscope. If any questions, pls visit: , videos showing the use of the conoscope. )
1	Turn on	Attach power cord and plug in the polariscope. On/off switch at the back of the polariscope.
2	Place stone	Gently place stone on removable lense. Some people prefer to use tweezers to hold the stone between the two filters. We find this requires 3 hands, and simply rest the stone on the removable lense.
3	Rotating Lense	Turn on polariscope. Look through the upper lense of the polariscope. Rotate the top lens until it is in the crossed position (dark.) Rotate removable lense exactly 1 full rotation. Results: Stone stays dark = Single Refractive (isotropic) Stone stays light = AGG Anything else (blinks or snake bands), take the next step:
4	Double Refraction Confirmation Test	Return the polariscope to the dark (crossed filter position.) Use the stone holder to turn the stone to its lightest position. Then looking down through the top filter, quickly turn the top filter 1/4 turn. Results: Stone becomes NOTICEABLY lighter = SR- ADR Anything else (stays the same, gets darker) = Double Refractive

Determining Refraction

Understanding your results:

Isotropic (single refractive or SR)-stays dark throughout a 360° rotation.

Anisotropic (double refractive or DR)-blinks 4 times,2 light and 2 dark during a 360° rotation .

Aggregate (AGG)-stays light throughout a 360° rotation

Anomalous Double Refraction (ADR) -twinkles instead of blinks. Looks like double refractive but is single refractive.

ADR is when a stone looks like it might be blinking, but really is just showing lighter where the stone is thinner or where there is a veil or weakness in the stone. Garnet and diamond sometimes display this phenomena. Tips! Be careful with using the polariscope for red / purple / orange stones. They often give confusing ADR results. Use your dicroscope or refractometer to confirm. Stones with very high RI's can also give misleading results.

Isotropic

Opal
Amber
Glass
Plastic
Diamond
Spinel
Garnet

Anisotropic

Zircon
Quartz
Beryl
Apatite
Corundum
Tourmaline
Topaz
Zoisite (Tanzanite)
Peridot
Orthoclase
Spodumene
Labradorite
Axenite
Mossenite (Syn. Diamond)