NM is marked on the bottom of this vintage frosted glass perfume bottle. It is in perfect condition and a high quality glass. I'm not sure if NM stands for Neiman Marcus. Neiman Marcus does put out limited edition perfume bottles. I researched this butterfly stopper and perfume bottle and came up empty. It is a very detailed stopper of the glass butterfly. It does have a plastic tip on the dauber, so it has to be from 1960's or later. The size of the butterfly perfume bottle is 2 3/4 inches by 1 3/4 inches at the widest part of the satin feeling frosted glass.
We always like to know the name of a perfume or where the bottle comes from, so we welcome more information from you, if you know more!!