It's still on the metal pin and covered with the usual soot and goo that time in service deposits on an insulator in service. The same collector sent me this one, for its provenance. The light purple glass was used in the 1960s, that should narow down its vintage. There are plenty pf porcelain power pieces on which the sections are of different colors, so this isn't a unique phenomenon. It's real, apparently there was no creative "Doctor Frankenstein" stuff done for this one