This is a vintage clear art glass duck figurine marked Art Vannes France in a diamond on the base. This mark was used by Cristalleries de Vannes-le-Châtel of France starting in 1960. The duck is 4 1/2" tall. The back of the duck is hollowed out, it could be used as an ashtray or a small candy dish. I have seen pictures of the same duck with a glass egg in the back, so it may have been intended as an Easter item. It is in very good condition. There is one tiny nick on the base at the back.
Cristalleries de Vannes-le-Châtel Art Glass France Duck Figurine