Hobbies And Interests
10X Loupe and Microscope
The loupe is the magnifier of choice for travel and ease of use, but loupes are usually 10X or at most 15X magnification. The microscope needed for gems magnifies at 40X, or 40 times the original size, according to the Gem Society website.
Refractometer or Polariscope
The refractometer measures the refractive index of a gem, and also measures birefringence and optic sign. Refractive index is the ratio of the velocity of light in the air to velocity of light in the gem. If the refractive index value of the ordinary ray is greater than the extraordinary ray, the optic sign is negative, and vice versa. Birefringence is double refraction, or the splitting of a light ray. The polariscope determines whether gems are singly or doubly refractive. It also measures the optic sign.
Lighting and an Ultraviolet Lamp
Quality lighting is necessary for gem identification. The polariscope usually has a light at the bottom and some microscopes provide lighting. An area light is an essential tool for gem identification. An ultraviolet light is handy in identifying gemstones, as some gems glow a different color in an ultraviolet light. There are inexpensive hand-held ultraviolet lights on the market that perform adequately for looking at gemstones.
Electronic Diamond Tester and Electronic Gem Tester
The diamond tester identifies diamonds only, but once you determine the gem is not a diamond, you can test for other gem qualities by other methods. The diamond tester is a hand-held tool that provides an on-the-spot shortcut to identification. Narrowing the field for a novice is helpful.
The electronic gem tester identifies groups of gems that have similar qualities to the tested gem. This tool works on thermal conductivity or the heat of a gemstone. Some gem testers have reflectivity or refractive tests also.
Books
Books are tools of convenience and necessity to the gemologist. "Handbook of Gem Identification" by Richard T. Liddicoat Jr. is a standard reference published by the Gemology Institute of America. Another helpful book is "Gem Identification Made Easy" by Antoinette Leonard Matlins, published by GemStone Press.
Gemology Tools Program
This computer program takes the results of your tests and reports the gem you have, based on the refractive index, single or double refractivity and specific gravity. This program saves time in the analysis, as shown on the International Gem Society website. Examples shown there do not require the optic sign, a time saver for identification.