VTG 60s cocktail mini dress rhinestone neckline, unlined, union made, size M

This dress was such a rare and fun find! A woman who has a Masters in Fashion in Textile History (and has worked in the garment industry her whole career) guessed the date of this dress in the late 60s. (Think Bewitched: Elizabeth Montgomery era.) There are NO tags (they were all cut out), so please consult measurements if you plan on wearing. Brand: Unknown Description: A late 1960's union-made cocktail dress. Without tags it is impossible to know the size or the materials, but I believe the material is satin. The union tag was partially readable. Aqua blue with hand-sewn rhinestones, the neck cuts into a V. The zipper is metal rather than plastic, and the dress is unlined since the wearer would have been wearing a slip beneath it. The hems are cut with pinking shears rather than finished. Size guesstimate: Medium Measurements: 18” pit to pit 13” center back to high point of waist 39” shoulder to bottom hemline A-line/Fit and flare NOTE: There are a few surface stains I've photographed. I didn't trust myself to stain treat them since the garment is over 50 years old Also, the beading may be fragile due to aged threads, handle with care. Condition: Preowned, Vintage condition Style tags: vintage, 60s, handmade, union, rare, unlined, I dream of Jeannie, costume, Halloween, collector, silky, satin, retro, 50s, cocktail, party, rhinestone, beaded, preppy, grannycore