We are going to conclude this series of four articles about the main Roman masonry techniques.
Oppus Scutulatum, Oppus Alexandrinum, Oppus Sectile. With these names the Romans designated a series of cladding techniques characterized by the use of marble as a building material. Unfortunately, the findings of Roman marbles in Europe are not abundant because during the whole Middle Ages they were used as raw material for obtaining lime, hence they were systematically destroyed. The reason is Roman marbles had almost always very good quality, with few impurities, being obtained from its calcination an excellent lime.
Photo 1.- Detail of Oppus Alexandrinum in the orchestra of the theater of Metropolis (Turkey).
The differences between these three techniques are not too great, consisting mainly of the size, shape and color of the marble pieces. Otherwise the construction system is identical in all three cases, similar to that of the Oppus Spicatum and Reticulatum: covering a central core of Oppus Caementicum.
Photo 2.- Oppus Alexandrinum on the pavement of one of the main streets of the ancient Tripolis ad Maeander (Turkey).
Photo 3.- High quality Oppus Sectile in the Byzantine church of Hagia Sofia (Nicea/Iznik, Turkey).
Specifying a little more, it can be said that the Oppus Scutulatum used pieces of rhomboidal marble - with which the result was somewhat similar to that of the Oppus Reticulatum - while the Oppus Alexandrinum made use of circular and