A Venetian Glass Goblet, c.1500 (XXVB92)
This remarkable goblet, with its layers of differently coloured glass, is an outstanding example of the skilfully made and imaginative products that epitomise ‘golden age’ Venetian and Venetian-style glass of the later 15th to early 17th centuries
The princely taste for exotic curiosities, including shaped and polished minerals, inspired Venetian glassmakers to make imitations, including cristallo for rock crystal and calcedonio for the banded chalcedonies (agate). A contemporary asserted that ‘…there is no kind of precious stone which cannot be imitated by the industry of the glass workers, a sweet contest of man and nature’.
Venetian calcedonio glass is first documented in a contract drawn up in 1460 between Taddeo Barovier and an apprentice. Taddeo’s brother Angelo seems to have been responsible for the development of calcedonio. He was probably the glassmaker Angelo who engaged in philosophical debate about combining and transforming metals, and, according to a contemporary source, ‘…variously and repeatedly experimented (and likewise, after him, his family) and reached supremacy with this type of work’. Although a Barovier speciality, calcedonio was also made in other workshops.
The variegated, swirling colours on the exterior of this goblet are typical of calcedonio glass, but the juxtaposition of contrasting areas of colour on the bowl is exceptional. The glass of the upper bowl and foot looks similar to the natural chalcedony nodule and slab displayed here. The nodule shows how the mineral occurs, while the slab is a cut and polished collector’s specimen. The lower, predominantly blue section of the goblet’s bowl may simulate an artificially stained agate. Since antiquity, agate has been artificially stained to extend the range of available colours. The bowl interior may replicate the mineral nephrite; a nephrite pebble is shown alongside. If the goblet originally had a cover, the contrast revealed when the cover was lifted would have been a delightful surprise.
Calcedonio was a labour-intensive, luxury product. Essentially, various metal oxides were added to a soda-lime-silica glass base. To obtain the swirling, variegated effects, ingredients that hindered the mixing of the glass constituents might be added and the glass was deliberately poorly mixed. A fascinating property of this glass is that it often looks fiery red when a light is shone through it.
- Suzanne Gaynor, Glass, Wallace Collection, London 1984 (available from the Wallace Collection shop)
- W. Patrick McCray, Glassmaking in Renaissance Venice: The Fragile Craft, Aldershot 1999
- Attilia Dorigato, Murano Island of Glass, Verona 2003
- Mineral specimens on loan courtesy of the Trustees of the Natural History Museum, London.