Carved with green tone jade, these small jade plaques have the shape of mask of Sanxingdui Culture style. With the size of 2cm tall and 1.5cm wide, these jade masks have convex plane shape. There is open work mouth and three holes with one on the top of back side and two on the cheek of the face. These jade plaques may be used as clothes decoration. It should be noted the the holes of the plaque as small as 0.1cm diameter. Antiquity evidences are additive crystal and calcification.