Product Review: No Name Refractometers
Beware of cheap "no name” refractometers (and their distributors). These tools may not be suitable for gem identification. Read our review to learn more.
2 Minute Read
Initial Impressions of No Name Refractometers
When I opened the package, one difference was apparent immediately. The “no name” instrument was much smaller than my GIA Duplex II refractometer. (See the photo above for a comparison). The hemisphere, lens, and light opening were less than half the size of the GIA unit. I expected this would cause problems. However, once I started my tests this turned out not to be the case.
First, I tested a number of identified faceted gems with established refractive indices (RI). To my surprise, I found the “no name” unit much easier to use than the larger Duplex II. The smaller hemisphere creates a smaller viewing area. Thus, the stone is centered automatically in the magnifying lens.
Compared to the Duplex II, this was a delight. With it, I usually start with the magnifying lens off. I get my head in the proper position to view the shadow and then replace the lens. With the smaller refractometer, all this was unnecessary.
Next, I tried doing some spot readings on cabochons. Here, the smaller and lower magnification lens really fell short. Getting an accurate spot reading from this little instrument proved…
Donald Clark, CSM IMG
The late Donald Clark, CSM founded the International Gem Society in 1998. Donald started in the gem and jewelry industry in 1976. He received his formal gemology training from the Gemological Institute of America (GIA) and the American Society of Gemcutters (ASG). The letters “CSM” after his name stood for Certified Supreme Master Gemcutter, a designation of Wykoff’s ASG which has often been referred to as the doctorate of gem cutting. The American Society of Gemcutters only had 54 people reach this level. Along with dozens of articles for leading trade magazines, Donald authored the book “Modern Faceting, the Easy Way.”
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