Two mink gowns were created

Two versions of the iconic mink gown were created. The first mink gown, lined with faux glass rubies and emeralds, cost $35,000 to make. It also has a jacket trimmed with mink. However, this dress was too heavy for dancing.

A second version of the mink dress was created, lined with sequins, which was lighter so that Ginger Rogers could dance in it. Both gowns are shown in the movie. The dress with the faux jewels was donated to the Smithsonian Institution.

Sources:

http://www.moviediva.com/website/MD_root/reviewpages/MDLadyinDark.htm

"Edith Head: the fifty-year career of Hollywood's greatest costume designer" by Jay Jorgensen. (Running Press, 2010). Page 104.