What a fantastic example of Art Nouveau! Though unsigned, we can attribute this piece to Liberty & Co. It's incredible enamel work on both sides of the brooch, as well as it's style, truly speak to the fine craftsmanship that Liberty & Co. was known for at the time. The entire piece is set in sterling. It features a natural pearl, bezel set in the center, with a milgrain edge. It measures 1 1/2" long and about 3/4" tall.