This gown went up for Auction at Julien's Live. The auction describes the gown as follows:
A Restoration period costume worn by Linda Darnell in Forever Amber (20th Century, 1947). Costume design by René Hubert. The velvet bodice is corseted with chiffon sleeves. The full skirt is created from a sheer fabric with a lace print layered over built-in petticoat. There are two bias labels in the skirt joined together, the first typed "12775241" and the other handwritten "504-30 Darnell." Accompanied by a copy of the film.