Vintage Crystal Cha Cha Brooch: Delizza & Elster Style - Etsy。This vintage accessory is a \"Cha-Cha\" style hair barrette or pin featuring aurora borealis (AB) crystals. The AB finish, developed by Swarovski and Christian Dior in the 1950s, gives the clear crystals an iridescent coating that flashes a rainbow of colors, including green, blue, pink, and purple, as light hits them. This pin is crafted on a silver-tone metal backing with a wire arm catch barrette mechanism. It features numerous faceted, geometric clear crystals that are clustered or suspended in a \"cha-cha\" style, allowing them to dangle and move freely to maximize sparkle.