Cameo glass

Cameo glass is a luxury form of glass art produced by etching and carving through fused layers of differently colored glass to produce designs, usually with white opaque glass figures and motifs on a dark-colored background. The technique is first seen in ancient Roman art of about 30BC, where it was an alternative to the luxury engraved gem vessels in cameo style that used naturally layered semi-precious gemstones such as onyx and agate. Glass allowed consistent and predictable colored layers, even for round objects.

From the mid-19th century there was a revival of cameo glass, suited equally to Neo-Grec taste and the French Art Nouveau practiced by Émile Gallé, and cameo glass is still produced today.

Despite the advantages described above, fragile Roman cameo glass is extremely rare - much more so than natural gemstone cameos like the Gemma Augustea and Gonzaga Cameo, which are among the largest examples of many hundreds (at least) of surviving classical cameos produced from the 3rd century BC onwards. Only about 200 fragments and 15 complete objects of early Roman cameo glass survive. The best and most famous example of these, and also among the best preserved, is the Portland Vase in the British Museum. Other fine examples, such as the Morgan Cup (Corning Museum of Glass), are drinking cups. Both of these named pieces show complex multi-figured mythological scenes, whose iconography has been much debated. The Getty Villa has another cup, and a perfume bottle with scenes of Egyptian deities, apparently an early instance of Orientalism. The Metropolitan Museum of Art in New York has a fragment over 11 inches (28 cm) long and 5 inches (13 cm) high from what was evidently an architectural revetment showing an acanthus frieze with eagles, the luxurious equivalent in glass of a "Campana relief" in pottery.

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