inlaying, process of ornamenting a surface by setting into it material of different color or substance, usually in such a manner as to preserve a continuous plane. Inlay is employed in connection with a great variety of objects, both of major architectural character and of minor furnishing and decorative function, and makes use of a wide range of materials, such as wood, stone, ivory, glass, metal, mother-of-pearl, and tortoiseshell. The art is of ancient origin and has been continuously and widely employed. The use of the word inlay is now more generally restricted to the true process as applied to furniture and other objects of wood and as distinguished from parquetry and the veneered work of marquetry. For stone or glass inlays, see mosaic; for metals, see niello and damascening; and for special wood inlays, see intarsia.