The Cargille Gem Refractometer Liquid has a refractive index of nD = 1.810, the highest of any liquid not containing arsenic. It is widely used with gem refractometers as a contact medium for the identification of gemstones. This light yellow liquid can also be used to reduce or eliminate glare from a gem's surface, facilitating inspection of the gem's interior for inclusions and other defects.
Remember that we offer a complete range of refractive index matching fluids.
This liquid is supplied in an amber glass bottle. The cap has a glass applicator rod attached to it on the inside, designed to deliver a small droplet.
To ensure the liquids maximum shelf life, keep this liquid tightly sealed after opening, store it away from direct light and in moderate temperatures.
nD = 1.81 +/- 0.005 @ 25°C
|Composition||Methylene Iodide with dissolved solids|
|Appearance||Golden yellow liquid|
|Color Stability||In sun: Will become very dark after I day
(Note: When stored in the dark the color is stabilized for up 5 years by the small piece of copper normally placed in the bottle by Cargille Labs)
|Index Change Rate by Evaporation||High: A 1/4 fl. oz. bottle open 5 days: full bottle changed +0.00130; half full (10 gram) changed +0.00207|
|Pour Point °C||< 20|
|Boiling Point °C @ 760mm Hg||> 180|
|Flash Point °C COC||None|
|Density g/cc @ 25 °C||3.135|
|Density Temp. Coef. g/cc °C||-0.0023|
|Coef. of Therm. Exp. cc/cc/ °C||0.0007|
|Viscosity centistokes @ 25 °C||2|
|Soluble: No common solvents|
|Partly Soluble: Acetone, Carbon Tetrachloride, Ethyl Ether, Methylene, Chloride, Toluene, Xylene|
|Insoluble, Ethanol, Freon TF, Heptane, Naphtha, Turpentine, Water|
|Clean Up: Wipe until dry with tissue, then use soap and water if further cleaning needed. Avoid letting liquid evaporate leaving crystals behind. To help remove crystals: Soak in soap and water or Carbon Tetrachloride or use of scouring pad when not injurious to item cleaned.|
|Compatibility: May soften some plastics (Especially Polystyrene, Polyethylene, and Polyurethane) and may affect epoxy, rubber (including Silicone and Neoprene), and will corrode Aluminum, Brass, Copper, and Steel|
|Toxicity Moderate (request MSDS)|
|Cauchy Equation: Refractive index as a function of wavelength at 25 °C|
|Source or||Wavelength||Refractive Index||% Transmittance 25 °C|
|Spectral Line||(angstroms)||25 °C||1 mm||1cm||10cm|
|Near UV cut off||4500||1.86||5||0||0|
|D (Na) D1, D2 mean||5893||1.810||98||82||14|
|Nd: YAG laser||10648||1.77||100||97||74|
|nF - nC||= 0.0448|
|Abbe vD: (nD - 1) / (nF - nC)||= 78.1|
|Temp. coef dnD / dt 20 - 25 °C||= -0.000680|