History of Marmorino
The origins of Venetian polished plaster
Marmorino is well known as a classic Venetian plaster; however, its origins are much older, dating to ancient Roman times. We can see evidence of it today in the villas of Pompei and in various Roman structures. In addition, it was also written about in Vitruvio’s “De Architectura”, a 1st Century B.C. history of Rome. Marmorino was rediscovered centuries later after the discovery of Vitruvio’s ancient treatise in the 15th century. This ‘new’ plaster conformed well to the aesthetic requirements dictated by the classical ideal that in the 15th century had recently become fashionable in the Venetian lagoon area.
The first record of work being done with marmorino is a building contract with the nuns of Santa Chiara of Murano in 1473. In this document, it is written that before the marmorino could be applied, the wall had to be prepared with a mortar made of lime and “coccio pesto” (ground terra cotta). This “coccio pesto” was then excavated from tailings of bricks or recycled from old roof tiles.
Marmorino in the city of Venice
The advantage of recovering scraps
At this point, to better understand the popularity of marmorino in Venetian life two facts need to be considered. The first is that in a city that extends over water, the transport of sand for making plaster and the disposal of tailings was a huge problem. So, the use of Venetian polished plaster was successful not only because the substrate was prepared using terra cotta scraps, but also the finish, marmorino, was made with leftover stone and marble, which were in great abundance at that time. These ground discards were mixed with lime to create marmorino.
A plaster that resists to dampness
Besides, marmorino and substrates made of “coccio pesto” resisted the ambient dampness of the lagoon better than almost any other plaster. In fact, on the one hand Venetian polished plaster is extremely breathable by virtue of the kind of lime used (the only lime which sets on exposure to air after losing excess water). On the other hand, the Marmorino substrate contains terra cotta, which when added to lime makes the mixture hydraulic. This means that it’s effective even in very damp conditions. In fact, terra cotta contains silica and aluminium, bases of modern cement and hydraulic lime preparations.
Instead of marble
The second consideration is that an aesthetically pleasing result could be achieved in an era dominated by the return of a classical Greco-Roman style allowing less weight to be transmitted to the foundation when compared to the habit of covering facades with slabs of stone.
Usually, marmorino was white to imitate the stone of Istria, which was most often used in Venetian construction, but was occasionally decorated with frescoes to imitate the marble, which Venetian merchants brought home from their voyages to the Orient. Indeed, in this fascinating period of the Republic of Venice, merchants felt obliged to return home bearing precious, exotic marble as a tribute to the beauty of their own city.
Marmorino maintained its prestige for centuries until the end of the 1800’s when interest in it faded and was considered only an economical solution to the use of marble. Only at the end of the 1970’s, thanks in part to the architect, Carlo Scarpa’s use of polished plaster, did this finishing technique return to the interest of the best modern architects.
At the beginning the industries were not interested in Venetian polished plaster which was only produced by artisans. Today, however, ready-to-use marmorino can be found, often with glue added to allow them to be applied on non-traditional surfaces such as drywall or wood panelling.