21mm Jeweler Loupe 10x Magnifier with LED and UV Light

The light is used for checking fluorescence in diamonds. Diamonds with fluorescence will appear cloudy when viewed with the light on. Fluorescence is not 'diagnostic' but, as with most tests, it eliminates some possibilities, opens other possibilities, suggests which other tests to carry out, and that's how gemologists identify stones.

Triplet Glass Lens 6 LED/UV Lighted 10x (21 mm) – SEP Tools

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21mm Jeweler Loupe 10x Magnifier with LED and Uv Light : : Electronics

21mm Jeweler Loupe 10x Magnifier with LED and Uv Light : : Electronics

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