Antonia Collection vintage luxury resort fiesta party dress

Antonia Collection high-quality off-shoulder dress for resort, fiesta, party, Hawaii. Made for I. Magnin luxury retailer (closed in 1995). Excellent condition, has had almost no use. Amazing quality tailoring. Great ruffles at shoulders. Somewhat abstract in intense colors, probably mostly cotton substantial fabric that holds its shape but I cannot find fabric tag. Lots of contrast piping. Shaped seams; Boning to support front. Lined to dropped waist. Vintage size 14. Armpit to armpit measured flat = 18” Back width between sleeve seams = 15” Length from approximate shoulder = 45” Back zipper length = 16”