Archaeological-revival gold and micromosaic 'Medusa' brooch, Castellani, before 1888, mosaic possibly by Luigi Podio

Another micromosaic brooch of Medusa, the mosaic by Luigi Podio, mounted by Castellani before 1888, is illustrated in the catalogue Castellani and Italian Archaeological Jewelry, The Bard Graduate Center, p. 174, fig. 6-35.

The technique of micromosaic was an 18th century development of an art that from Greek and Roman times had been used to decorate the floors and walls of villas, palaces and early Christian churches. These early mosaics were made of pieces of stone cut in the shape of cubes called tesserae. Between the 4th and 6th century AD mosaics made of small cubes of multicoloured glass were used to decorate Christian churches. By

the 11th century, Ravenna had become the centre of mosaic production, soon joined in this status by the glass mosaic workshop of St Mark Basilica in Venice.  In the 16th century craftsmen from the workshops of St Mark and Ravenna were summoned in Rome to contribute to the building of St Peter’s Basilica. The mosaico piccolo or micromosaic technique started to develop in the Vatican Mosaic Workshop in the late 18th century. The size of the smalti, the multicoloured tesserae used to create these mosaics was minute: in the best examples up to 5000 per square inch. The name smalti is the Italian for ‘enamel’, the material composing the micromosaic tesserae made at the Vatican Workshop. Smalti were first formed into cakes out of which chips were broken off, molten in a furnace and then pulled with tongs to produce filaments known as filati. Mosaic artists would then break the filati in shorter segments and arrange them with tweezers onto a base coated with a slow drying adhesive. The base generally consisted of a copper tray of suitable shape but also slabs of marble, hardstone or glass were hollowed out and used as supports. The multicoloured tesserae were used much like a brushstroke in a painting to give shape to chosen decorative motif. When complete the mosaic surface was polished and the gaps between the tesserae filled with wax. In the early part of the 19th century the art thrived: jewels and snuff boxes decorated with micromosaics were highly sought after by collectors all over Europe. Subject matters varied from realistic animals and basket of flowers to Roman archaeological ruins and landscapes. By the mid 19th century, however, inspiration was languishing and technical quality faltering. This is when Castellani started to turn attention to this technique, encouraged by Michelangelo Caetani Duke of Sermoneta and by the Russian count Vassili Dimitrievitch Olsoufieff, an ancient art scholar. Castellani promoted a return to technical quality and a change in subject matter. Predominatly inspired by early Christian examples from Rome and Ravenna Castellani’s micromosaics were made under the guidance of Luigi Podio who presided over the mosaic workshop between  1851 and 1888 and guaranteed a consistent outstanding quality of production. It is generally accepted that the Castellanis played an important part in the process of raising the level of the art of the mosaic above the banality and coarsness of contemporary production.