
Standard Loupe for Gemologists and Jewelers
Table of Contents:
The 10X Loupe Standard For Evaluating Gems
How to Use a 10X Loupe
Examining Gem Exteriors with a 10X Loupe
Surface Observations
Girdle
Facets
Culet
Examining Cabochons with a 10X Loupe
Examining Inclusions with a 10X Loupe
Fractures
Mineral Inclusions
Voids
Healing Fractures
Other Inclusions
Evaluating Coloring with a 10X Loupe
Zoning
Banding
The 10X Loupe Standard For Evaluating Gems
Loupes come in several varieties. Watchmakers prefer the kind held by the eye socket. Other professionals prefer loupes worn like eyeglasses or clipped onto glasses. Some types sport fancy features like illumination and built-in tweezers. Gemologists prefer the hand loupe.
For gemologists, the 10X loupe (with ten-power magnification) is the standard for hand-held gem identification. Although you’ll find more powerful loupes, the depth of field (the area that’s in focus) is so small above 10X that they’re hard to use. Instead, use a microscope when you need higher magnification. With lower-powered magnification, you just can’t see as much detail.
You may encounter the following terms when shopping for a 10X loupe.
Triplet: a loupe with three lenses, which reduces distortion around the edges.
Color correction: a special lens coating to ensure you see natural colors, not colors distorted by passing through the loupe.
These features increase the price.
The standard for judging diamond quality is what an expert can see in good lighting with a triplet, color-corrected 10X loupe. Gemologists use this same standard for evaluating colored stone quality, too. However, you don’t need to purchase such an expensive variety for your gemological studies. You can get as much information and enjoyment from a less expensive model.
Ref : https://www.gemsociety.org/article/10x-loupe-the-gemologists-best-friend/
https://thejewelryloupe.com/how-to-buy-a-jewelry-loupe/
