How does the UV yellow reactive ink work? 0

[GoldIsBack.com]

I've read that NGC labels have UV yellow reactive ink. Does this mean that the label will glow in the dark when using a black/UV light? Do all NGC labels have reactive ink? If I find a NGC holder that the label does not glow with a black light, does this mean it is a fake?

Thanks

[Conder101]

UV ink means that it has a compound in it that when exposed to UV light absorbs some of the energy causing electrons to rise to a higher energy state. As the electrons return to the lower energy state they emit photons of visible light.  The frequency/color of this light depends on the compound used.  They do not "glow in the dark", they only emit the light while they are being exposed to the UV.

If NGC slabs now include this feature it is most likely a recent development and older slabs will not react to the UV.  That doesn't mean the older slabs are fakes.

[Conder101]

Sorry for the double post, had an internet error.

Edited December 8, 2020 by Conder101