Item Description: 3.6ml Vial of 1.800 Refractive Index Fluid for Gem Refractometers, 16 Grams (3.6ml) THIS PRODUCT DOES NOT CONTAIN ARSENIC AND IS NON-POISONOUS. CAN YOU SAY THAT ABOUT THE OTHER STUFF ONLINE? THIS GEM REFRACTIVE INDEX FLUID IS AMERICAN MADE, SO YOU KNOW IT'S ACCURATE! WE OFFER THE LARGEST SIZE AVAILABLE ANYWHERE! OUR 3.6ml VIAL WEIGHS 15 GRAMS! Specifications (DO THE OTHER GUYS DO THIS?): Refractive Index @ 25'C: nD = 1.800 +/- 0.005 @ 25C Appearance and color: Burgundy liquid Boiling Point at 760 mm Hg: 181 C (358 F) pH: Not applicable Vapor Pressure: 760 mm Hg @ 23 C/73 F...1.5 Viscosity: Not applicable, but close to an ISO 5 Specific Gravity (water = 1) @ 23 C/73 F: 3.08-3. Water solubility: Slight Octanol/Water Partition Coefficient in Kow: Specific value not known Flash Point: 230'F (110'C) Evaporation Rate (mineral oil = 1, 760 mm Hg, 73 F/23 C): 1 This product is the perfect ECONOMY RI Fluid! The product will not allow your refractometer to read between 1.801 - 1.810 Refractive Index. How many Gemstones will you NOT be able to test? The answer? 2 stones. Both Single Refractive: Spessartite Garnet (1.81 +/-0.10) and Gahnite, aka Blue/Green Spinel (1.80). 99% of the other stones you can read! This product is designed to be a cost effective alternative to the expensive 1.81 RI Fluid. Perfect to testing ALL of your stones, while you save the good stuff (1.81RI Fluid) as a backup in case you find a blue/green spinel! The most important aspect of the Refractometer is the quality of the fluid and its Refractive Index. This product has a Refractive Index value of 1.800RI and is THE most economical product for accurate GEM Identification. The 4.0ml Vial holds about 3.6ml of product. The Gem Refractometer Liquid has a refractive index of nD = 1.800, the second highest of any liquid not containing arsenic. As the name implies, it is widely used with gem refractometers as a contact medium for the identification of gemstones. This Burgundy 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. This liquid is repackaged and supplied in an amber glass vial with applicator rod. Vials are filled 7/8 full and contain 3.6ml of solution. To ensure the liquids maximum shelf life, keep this liquid tightly sealed after opening, store it away from direct light and in dry moderate temperatures. This product is the non-poisonous version of the classic Gem Refractive Index Fluid; Diiodomethane (methylene iodide). It is not carcinogenic (won't cause cancer) according the the product MSDS. National Industrial Supply 30777 Rancho California #891420 Temecula, CA 92589, USA Sales: 951.308.9269 - Fax: 310.733.5480 - E-mail: nisupply@gmail.com - Website: www.nisupply.com