This panoramic view of the Roman Forum, known in earlier centuries as the Campo Vaccino, or cattle market, is made from hundreds of pieces of inlaid enamel glass in a medium known as micromosaic. Seen from right to left, the colonnade on the right is the Temple of Saturn; the smaller one to its left is the Temple of Castor and Pollux; the obelisk in the distance is the Column of Phocas, the last addition to the Roman Forum in 608 A.D.; to its left is the Arch of Septimus Severus, and beyond that in the left background is the dome of the church of Saints Luke and Martina.
The ancient mosaic technique was brought to Rome by artisans from Saint Mark’s Basilica in Venice, the center of mosaic work in Italy, in the late 16th century. As great Renaissance paintings on the walls of Saint Peter’s Basilica began deteriorating from environmental conditions, church officials decided to replace them with mosaic replicas and relocated the canvas originals elsewhere in the Vatican. At this time, Pope Gregory XIII (r. 1572 – 85) also commissioned new mosaics in the domes and chapels of St. Peter’s.
In the early nineteenth century, several of the artisans trained at Saint Peter’s Basilica began opening private micromosaic shops in Rome, concentrated in the area of the Piazza di Spagna, to capitalize on the flourishing tourist market and the demand for souvenirs of the major Roman landmarks. Victorian travelers who could afford micromosaic views were drawn more towards the colorful, exquisitely crafted scenes than the neoclassical etchings of Piranesi favored by their predecessors.
While ancient mosaics employed square stone pieces known as tesserae, their Victorian descendants were made from much smaller pieces of opaque enamel called smalti, created in the form of long thin tubes called filati that were cut and set into a slow-drying oil-based mastic which allowed the artist more time to work on his composition. By the 18th century the artisans had developed more than 28,000 different tints which enabled them to create subtle tonal ranges approaching those of oil painting.