Signorina Concha de Ossa, Giovanni Boldini; pastel on prepared canvas, roughly 87 x 47 inches (221 x 120 cm). LInk is to Wikimedia Commons, which sourced the image from a past sale of the painting from Christie’s. I don’t know the location of the original, likely a private collection.

Italian painter Giovanni Boldini, who was active in the late 19th and early 20 centuries, shifts here from his usual oils to pastel, but the piece is in keeping with his series of full length portraits of society women in flowing gowns.