The Glass from the Gnalić Wreck, Croatia - Part II
The largest category of glass found consisted of vessels (in excess of 4,000 individual items) and these were predominantly tablewares. These included vessels decorated with exceptionally high-quality and detailed diamond-point engraving. Their consistent style and the repetition of identical motifs, suggests that these were the product of a single workshop, and it is indeed likely that this was Venetian. Other forms were of a less certain provenance. Some, such as a group of lidded tankards may have been produced in Italy but for a foreign market. However, these constitute only a small portion of the total assemblage. The largest group of drinking vessels, and with over 3,000 examples were goblets with a folded foot and either plain or mould-blown bowls. The poorer quality of the glass of these vessels, as well as their often careless construction, suggests a more provincial manufacture, and it is possible they originated in Dubrovnik , which was known to have its own industry at this time.
Whilst the vast majority of the vessels could be shown to belong to a relatively few well-defined categories, there were some smaller groups of glass which were much more unusual. Perhaps one of the most interesting of these was a number of coloured oval bottles and shallow small bowls that were distinctly un-European in style. The most striking of these were decorated with blobs of coloured glass which were `marvered' or smoothed into their surfaces. Plainer, but no less unusual, were over 40 examples of plain blue oval flasks with a distinctive `stepped' rim. All of these vessels cannot be paralleled by examples from known centres of Western European glass production, and at this stage it seems most likely that they were Islamic in origin, although their presence, albeit in relatively small numbers, on what had been previously assumed to be a Venetian galley is curious. Certainly they confirm that the cargo consisted of a more complex mixture of vessels that originally first thought!
As well as vessel glass, over 750 circular window glass `crowns' were found. As well as nearly 600 circular and rectangular mirror glass plates. The window glass was made by blowing and opening out a bubble of glass on the blowing iron, and then spinning it so the centrifugal force created an even-shaped disc. In Mediterranean regions these were usually made quite small, such as the Gnalic examples, and incorporated into glazing pattern whole, but would have only been used in churches or the more wealthy households.
The mirrors found were all made by a more laborious process, to ensure that the glass was of sufficient flawless quality to reflect without distortion. A thick sheet of glass was first cast into the approximate shape and once cooled its surfaces were ground smooth. Contrary to popular belief silver was not used to make them reflective, rather an amalgam of tin and mercury. Amazingly this remains on some of the examples from Gnalic, but what is also interesting is that it is apparent that unground and unfinished mirror plates were also being transported presumably for retail and final preparation elsewhere.
The research into the glass from the Gnalic wreck is still ongoing and further analysis will provide further insight into the provenance and destination of many items of the cargo. This work will be finished during the course of 2006 and published as a monograph.