To provide exhibition of excellent decorativeness, persistence of ornamental functions for a long period and an improvement in usability.

An upper layer 7 which has transparency or translucency to the extent of making at least its inside surface visible has, in its lower position, a lower layer 5 which has a surface form different from the surface form of the upper layer 7 and permits the visual perception of the surface form through the upper layer 7 therefrom. The lower layer 5 and the upper layer 7 are formed of materials varying in vibration characteristics.