Joined: 12 Mar 2009
Location: Southport, UK
|Posted: Tue Oct 14, 2014 10:10 pm Post subject: Phosphors and Fluors
|OK just to keep me absolutely sane as my head it going round in circles trying to get this right.
When I longwave some of the newer security stamps they glow bright yellow but under shortwave they show blue is it normal for most of the modern stamps to always have the Yellow AY AY2 AY3 under longwave but be Blue under shortwave?
I can't seem to find any older 1993 > stamps with a Yellow Fluor and Yellow Phosphor
Don't think of a stamp to lick with your spit,
Think of the effort that's gone into it.
Sticking it on an envelope may cause dismay,
Until a collector removes it one day.