I really like the new 2017 NIA commemorative insulator. The chemistry of the insulator's glass is very interesting since it contains neodymium. Under sunlight, the insulator is pink, but under the light from a high intensity mercury vapor lamp, the insulator is an bright electric blue! Nice color! I think it has to do with the absorption of infra-red rays from the sun or incandescent lamps. Fluorescent lamps and mercury vapor lamps do not contain infra-red rays in their spectrum. Fluorescent lamps do contain red rays, but it's only in the visible spectrum range, not the infra-red range.