This large and exceptionally detailed micromosaic depicts St. Peter's square with the domed Basilica and Vatican beyond. Popular with tourists the vista was favoured by mosaicists during the nineteenth century but it is rare to find an example of such proportion and detail. The square is richly peopled with bustling figures and provides a fascinating snapshot of how the piazza must have looked to the visiting Grand Tourist. Details include the papal carriage, in which the Pope is shown illuminated by a golden halo, traveling across the square, perhaps on his way to give an address from the balcony, shown to the bottom left of the panel beneath which Savoia guards stand on parade.
The scene is also fitting given that mosaic, a traditional medium for pictorial decoration in early Christian churches, was revived at the end of the sixteenth century for the decoration of St. Peter's basilica. The Vatican brought an unknown mosaicist from St. Mark's in Venice to execute mosaics for the domes and chapels of St. Peter's and thus established the Vatican mosaic workshops which remain in operation to this day. For large scale mosaics the workshop originally used cubic tesserae, known as smalti, made from ground glass and baked in an oven like enamel. By the 1760s this art had been so perfected that it was possible to produce rods or threads of coloured glass, called smalti filati, thin enough to be cut into the minute tesserae used on the present lot. These tiny individual tesserae in an almost limitless palette of as many as 28,000 colours allowed truly painterly compositions. The painstaking detail required to work micromosaics meant the smallest were set into snuffboxes and jewellery whilst larger tables or plaques were massive undertakings. By the 19th century the Vatican workshop was producing such superior mosaic-work that it operated at the near exclusion of any other mosaic studio.
The master mosaicist Cesare Roccheggiani was active at the Vatican workshops from 1856 to 1864 but like many of his contemporaries sought to supplement his meager income by establishing his own workshop making mosaics for dealers and tourists. His private atelier is recorded firstly at 125 Via Babuino and then, by 1874, at 14 & 15 Via Condotti (J. Gabriel, The Gilbert Collection Micromosaics, London, 2000, p. 289). By this time there were as many as ninety-six Mosaicisti operating in Rome largely producing small plaques, miniatures and cameos for the tourist trade. The best workshops continued to produce micromosaics on a massive scale but such magnificient and costly examples as the present lot remained the preserve of the wealthy and powerful. Monumental mosaics were bought as souvenirs by visiting aristocrats, given as diplomatic gifts, commissioned by monarchs and displayed at the Great Exhibitions. A comparable mosaic, smaller in size, showing St. Peter's Square during the Benedizione Papale is illustrated in R. Grieco, Micromosaici Romani, Rome, 2008, p. 174.