STUCCO, is a plaster of any kind used as a coating for walls, and to give them a finished surface. Stuecatura, or stucco-work, is the term employed for all interior orna mental plaster work in imitation of carved stone, such as the cornices and mouldings of rooms, and the enrichments of ceilings. Stucco was very much employed by the ancients, and not merely for coating columns, &c., constructed of brick, but in many in stances for covering stone, or even marble: for which last purpose it was applied so sparingly as to be no more than a very thin incrustation, for the purpose, it is now sup posed, of being painted upon.
The stucco used for internal decorative purposes, such as those above mentioned, is a composition of very fine sand, pulverised marble, and gypsum, mixed with water till it is of a proper consistency. Within a short time after being first applied, it begins to set, or gradually harden, in which state it is moulded, and may at length be finished up with metal tools.
The stucco employed for external work is• of a coarser kind, and variously prepared, being now manufactured wholesale as an article of commerce, ready for use ; and of which the different sorts are generally dis tinguished by the name of cements. or Liardet's Cement is an oil-cement, of which the chief ingredients are fine whiting and calcined oyster-shells, well mixed and ground up in a mill with oil. Parker's or Roman
Cement, that now most in use, consists chiefly of a preparation of argillaceous limestone found on the coast of Essex and Kent, and in the Isle of Sheppey. Of Bailey's Cement lime and sharp sand are the principal ingre dients. _Mastic Cement, or Tlamelin's Cement, is composed of peroxide of lead and oil; Keene's Cement is one of 'recent invention, and of very superior quality, tailing a surface and polish almost equal to that of the finest marble; it is in fact a species of scagliola ; consequently it is employed, like that, only for interior decoration. Almost every year produces some new kind of stucco.
If perfectly well executed, stucco will be nearly equal in appearance to stone, and even superior to that of stone of inferior quality. There are some who protest against the use of stucco externally, as a spurious and mere tricious mode of building with sham material; but it is certain that most of Palladio's edifices, and of what are spoken of as the marble palaces' of Venice and Rome, are merely faced with stucco.