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Handheld ASET®

The AGS Handheld ASET®, though less exacting than its larger counterparts, is the right size to have with you any time you need the support of light performance technology.

The handheld ASET® is easy to use on loose or mounted diamonds, and is convenient for travel. Simply hold a diamond (in tweezers) centered and flush with the rim and position the cone so that maximum light enters it.

When a diamond is viewed through the ASET®, a color-coded image is seen. The different colors show the angles from which the diamond gathers light.

Green = 0º (horizon) to 45º
Red = 45º to 75º
Blue = 75º to 90º
Black or White = indicates leakage


Red represents light coming from angles where there is likely to be bright, direct sources of illumination in most viewing environments. This color is dominant in the ASET® image of a well-cut diamond.

Blue corresponds to light that normally is blocked by the viewer’s head and body. An ASET® image with a moderate amount of this color in an attractive pattern means the diamond has good contrast.

Green is produced by low-angle light, which usually is reflected from walls or other objects in the surrounding area (rather than coming from direct sources). A diamond with a high cut quality may show small amounts of this color around the bezel area of the ASET® image.

Black or White appears in areas that do not return light under real-life viewing conditions. If a diamond is well cut, the ASET® image will show only very small areas of black or white around the outer edge (and perhaps none).

Handheld ASET®
Member Price: $25.00
Non-Member Price:  $50.00

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U.S. Patent Nos.: 7,336,347 – 7,355,683 – 7,372,552 – 7,382,445 – 7,420,657