Unguentaria were amongst the most common objects of Roman blown glass: produced in large numbers, they were items of everyday use for keeping expensive perfumes and cosmetic oils. The small body and mouth were ideal for slow, careful pouring, while glass was preferred for holding liquids, due to its non-porous, non-absorbent nature.
The invention of glass-blowing revolutionised the art of glass-making in the 1st century BC. The new technique allowed craftsmen to use smaller amounts of glass for each vessel and obtain much thinner walls, so enabling the creation of small medicine, incense, and perfume containers in new forms. Different minerals were added to create a variety of colours; the blue tint seen in this piece would have been created by adding copper or cobalt and changing the oxygen levels. These small glass (or ceramic) bottles are found frequently at Hellenistic and Roman sites, especially in cemeteries, and the perfumes which filled them would have been gathered from all corners of the expansive Roman Empire.
To find out more about Roman glass please see our relevant blog posts: Ancient Glass and Collecting Guide: Ancient Roman Glass
