BCBGMAXAZRIA Dress Black Large ribbed high neck fabric is magic

BCBGMAXAZRIA Black Dress Large The material tag is 79% silk 19% nylon 2% Spandex I'm confused by the silk but it is a very nice stretchy but quality sweater type material slinky and heavy Ribbed and high neck because of its heaviness and stretch fits my teen fine and she's a small and fits me as xl, I'd say it would stretch to 3x, it's just some kind of wonder fabric, stays heavy and nice even w stretch. Ribbed and detail line is flattering down the dress sleeveless cut at a flattering angle