HIST363: Global Perspectives on Industrialization

Cast Glass Patterns

Ribbed bowl of mosaic glass in the Metropolitan Museum of Art

The Lycurgus Cup, a dichroic (colour-changing) cage cup, lit from behind, with a modern foot and rim.

The glass sheets used for slumping could be produced of plain or multicoloured glass, or even formed of 'mosaic' pieces. The production of these objects later developed into the modern caneworking and millefiori techniques, but is noticeably different. Six primary patterns of 'mosaic' glass have been identified:

• Floral (millefiori) and spiral patterns: This was produced by binding rods of coloured glass together and heating and fusing them into a single piece. These were then cut in cross-section, and the resulting discs could be fused together to create complex patterns. Alternately, two strips of contrasting-coloured glass could be fused together, and then wound round a glass rod whilst still hot to produce a spiral pattern. Cross-sections of this were also cut, and could be fused together to form a plate or fused to plain glass.
  
  
• Marbled and dappled patterns: Some of these patterns are clearly formed through the distortion of the original pattern during the slumping of the glass plate during melting. However, by using spiral and circular patterns of alternating colours producers were also able to deliberately imitate the appearance of natural stones such as sardonyx. This occurs most often on pillar-moulded bowls, which are one of the commonest glass finds on 1st century sites.
  
  
• Lace patterns: Strips of coloured glass were twisted with a contrasting coloured thread of glass before being fused together. This was a popular method in the early period, but appears to have gone out of fashion by the mid-1st century AD.
  
  
• Striped patterns: Lengths of monochrome and lacework glass were fused together to create vivid striped designs, a technique that developed from the lace pattern technique during the last decades of the 1st century AD.

The production of multicoloured vessels declined after the mid-1st century, but remained in use for some time after.

Gold Glass

Detail of a gold glass medallion with a portrait of a family, from Alexandria (Roman Egypt), 3rd–4th century

Gold sandwich glass or gold glass was a technique for fixing a layer of gold leaf with a design between two fused layers of glass, developed in Hellenistic glass and revived in the 3rd century. There are a very fewer larger designs, but the great majority of the around 500 survivals are roundels that are the cut-off bottoms of wine cups or glasses used to mark and decorate graves in the Catacombs of Rome by pressing them into the mortar. The great majority are 4th century, extending into the 5th century.

Most are Christian, but many pagan and a few Jewish; their iconography has been much studied, although artistically they are relatively unsophisticated. In contrast, a much smaller group of 3rd century portrait levels are superbly executed, with pigment painted on top of the gold. The same technique began to be used for gold tesserae for mosaics in the mid-1st century in Rome, and by the 5th century these had become the standard background for religious mosaics.

Other Decorative Techniques

A number of other techniques were in use during the Roman period, including enamelled glass and engraved glass.