Se faire un visage de bois
This French expression means to take on a closed and cold facial expression, not to be confused with avoir la gueule de bois (to have a hangover). Another fitting but simple expression for this sculpture, which is a part of the primitive art collection at the Musée du Quai Branly, Paris, is faire face (to face).
un visage: a face
une gueule: a face, e.g., "mug" (slang)
de bois, en bois: wooden