Unguentaria were amongst the most common objects of Roman blown glass: produced in large numbers, they were items of everyday use for keeping expensive unguents and cosmetic oils. By the 1st century AD, the technique of glass-blowing had revolutionised the art of glass-making. 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. The small body and mouth allowed the user carefully to pour and control the amount of liquid dispensed, and glass was the material of choice for storing the oils because it was not porous. 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. Originally, much of Roman glass vessels were modelled in bluish-green translucent colour, which resulted from the iron oxide present in the silica or the sand. However other metal oxides were added to the glass to give it different bright colours; in the case of this beautiful example, cobalt would have been added to the glass to create an intense royal blue colouration.
To find out more about Ancient Roman glass please visit our relevant blog post: Ancient Roman Glass.