日月星水晶屋 Sun Moon Star Crystal House 日月星水晶屋 Sun Moon Star Crystal House Sun Moon Star Crystal House | About Us Sunn Moon Star Crystal House‧Gemmological Instruments Payment & Shipment Gift Advice New Products Chinese
five elements birthstone astrology wealth career&study love wisdom health emotion home
origin function structure cleaning chakra special items gemstone treasury
Sun Moon Star Crystal House |  Mineral TreasuryJewelry CareWedding Anniversary Back to Black
alexandrite
 
 



What is UV light: Ultraviolet (UV) is electromagnetic radiation with wavelength from 10nm to 400nm, shorter than that of visible light but longer than X-rays.
UV radiation is present in sunlight, and constitutes about 10% of the total electromagnetic radiation output from the Sun.
UV light can cause chemical reactions and causes many substances to glow or fluoresce.

In gemmology, two energy levels of UV light are used:
Long wave ultraviolet (LWUV) 365nm | Short wave ultraviolet (SWUV) 254nm

Visibility: Ultraviolet rays are invisible to most humans. The lens of the human eye blocks most radiation in the wavelength range of 300-400nm; shorter wavelengths are blocked by the cornea. Humans also lack color receptor adaptations for ultraviolet rays.

UV in Gems world: In gemstone world, different minerals may exhibit different fluorescence or phosphorescence reaction under UV. Other than the beauty that it gives out, it can be used as a back-up to identify the gems.

Luminescence: it describes the emission of 'cold', non-incandescent visible light by a substance. Both fluorescence and phosphorescence are kind of luminescence.

Fluorescence: It is the emission of visible light by a substance while it is being illuminated by radiation of higher energy. And the effect will exhaust once the outside influence is removed.

Phosphorescence: is a type of luminescence, phosphorescent materials continue to emit radiation after the removal of the source of irradiation.

 

UV fluorescence minerals
紫外光螢光礦物



UV machine

紫外光燈



專業365nm紫外光手電筒
Professional
365nm UV Light Torch


fluorescence & phosphorescence
What's the difference?


Reference: https://en.wikipedia.org/wiki/Ultraviolet;
 
Precaution of using UV:
1. Gem material should be thoroughly clean
2. It would be placed on a black, non-reflecting pad
3. It can be harmful to the skin and dangerous to the eyes, these UV lamps should never be looked at directly.
4 SWUV can be dangerous. Use with care and only after instruction.
5. Fluorescence effect is best seen in an environment which shielded from surrounding light.
Address: B26, 1/F, San Po Kong Plaza, 33 Shung Ling Street, San Po Kong, Kowloon, HK
Google Map email  
SunMoonStar CopyrightSun Moon Star Crystal House. All Rights Reserved.      Designed by Sun Moon Star Design House