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Alexandrite

Tsarstone collectors guide


Ultraviolet lamp

Ultraviolet lamp
A mercury discharched lamp in quartz glass designed to produce ultraviolet light for exciting luminescence in gem minerals specially diamonds. The long-wave lamp is provided with wood's glass filter to emit wavelengths between 400 nm and 300 nm. To obtain short-wave wavelengths a low pressure mercury lamp, which emits lines at 253.7 nm by means of a suitable filter or a Chance OX7 filter. Mostly ultraviolet lamps are provided with combination of both SWUV and LWUV.
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