Glass was often the preferred material for storing expensive oils, perfumes, and medicines because it was not porous. The small mouth allowed the user to carefully pour and control the amount of liquid dispensed. By the 1st century AD, the technique of glass-blowing had revolutionised the art of glass-making, allowing for the production of small medicine, incense, and perfume containers in new forms. These glass bottles are found frequently at Hellenistic and Roman sites, especially in cemeteries, and the liquids which filled them would have been gathered from all corners of the expansive Roman Empire. Different minerals were added to create a variety of colours; the yellow tint seen in this piece would have been created by adding antimony and lead.
Trail decoration is an embellishment technique which was a popular feature of Roman glass artefacts, and was composed of a strand of glass applied to a vessel or object. Narrow trails of coloured glass were applied in zig-zag or festoon patterns to vessels; trails of varying thickness were frequently added as rims, handles, or base rings. Trails were also used as surface decoration, usually in a spiralling pattern around the vessel which was either raised or made from a different colour of glass.
The iridescence on ancient Roman glass was unintentional, and was caused by weathering on its surface. The extent to which a glass object weathers depends mainly on the burial conditions; however, the humidity, heat, and type of soil in which the glass was buried also all affect its preservation.
To find out more about Roman glass, please see our relevant blog post: Ancient Roman Glass and Collecting Roman Glass.
