Thanks David, I did not know about darker colors getting darker with exposure to sunlight. I just assumed everything faded.

Another question, do you know when Paulson introduced UV stamps/marks to their chips. It seems to me the smallest H&C mark was the first occurance but nailing down a year seems very hard. Any ideas? Reason I ask again is that if N1360 is indeed 1979 that would seem to be one of the earliest examples of a UV stamp used??

Cheers, Tim.