Roman glass and its spread throughout the Empire: decorative elements

In the second century of our era glass also inspired to a Greek poet, Mesomede already freedman of the Emperor Hadrian, some verses in which he describes the process of fusion of quartz pebbles or maybe even rock crystal pebbles, used as we have seen in a previous article, to obtain a white and transparent glass.



Ancient Roman glassware in transparent white and pale colours



The decoration is by winding wires in crossed lozenges, or in diamond shape, often shot around the neck, by coloured glass, in drops, spots, ribs and depressions or reliefs obtained with pliers, to grinding, to engravings by wheel and sometimes in pointed diamond shapes. These decorations are alone or associated with mythological scenes and in later centuries with hunting, chariot races, gladiator fights, and even with Old and New Testament scenes.

complex decorations in the surface of the glass obtained with depression and relief techniques

Roman glass bottles with complex handles

The decoration is made with motifs painted by enamel or more often cold-finished, by gold-leaf engraved with ivory tip and inserted between two layers of glass welded together by fire (this technique occurs in many so-called "glass of martyrs" or "orbicular", which are bottoms of shallow bowls found embedded in the concrete of niches of catacombs, with scenes taken from Jewish and early Christian symbolism, or in the production of round beads that still are made by glass jewelers in Murano to give the glass beads for Pandora superior brightness thanks to the outer layer of crystal covering the gold leaf).

ancient Roman glass plate gold-leaf engraved with ivory tip

ancient Roman glass beads

But the summit of the decorative ability was reached in those little loop-shaped cups, sometimes in forms of buckets ("situlae") on which with a most patient work, the grounds were obtained by digging all around the surface and leaving only the thin struts that held the decoration adheres to the glass bottom, for which the vessel was formed by two layers, of which the outer perforated as a network. Beautiful the greenish sample of II-IV century with a hunting scene, in the Treasury of San Marco in Venice, where he also preserves a valuable situla violet in color, probably a Egyptian manufacturing from the same era, engraved with a Dionysiac scene.

Roman glass situlae with complex decorations

situlae greenish in colour (type diatreta) with hunting scenes and Dionysian scenes. Venice, Treasury of San Marco

Winckelmann, with a strict interpretation of a term half Greek and half Latin used by Martial and by Digesto, called them "diatreta", but with more ground before him, Celio Rovigo and Salmasio argued that "diatreta" was not a voice specific for drilled glass, but generic with which it is formerly designated all sorts of cut glass and to substantiate that claim there is the name of "diatretarii" given to a corporation of craftsmen of the glass, as opposed to the other called "vitreari", and the large number of glass objects carved and turned by the wheel left to us from the Roman world.

Roman glass "diatreta"

Roman glass: "diatreta" cup

So while the "vitreari" manufactured and formed the blown glass, the "diatretarii" worked it in various ways by carving, decorating it with pods, ovals, circles, facets and all those motifs derived from the art of lapidary for mimic the effect of precious stones, especially of rock crystal, which are still applied today almost without substantial variations on that heavier type of glass that is closest to the real crystal which is also called by this name.

Roman glass: rock crystal objects

As documented by Martial, the "diatretarii" of Alexandria in Egypt, who lived on the Tiber river in Rome, had established all their workshops at the Circus Flaminius, but the objects made in the “Urbe”, in laboratories where the work was limited to pure carving, were, according to the poet, very coarser than those that were produced in the workshops of Alexandria, because here the carver worked side by side with the formator and the work that came out of their hands so acquired, right from birth, a perfect harmony between form and decoration. The "vitreari" instead had their furnaces, at the time of Alexander Severus (222-235), on Monte Celio in Rome.

reconstruction of the Circus Flaminius as it appeared in ancient Rome

Here you find the full History of Murano glass