A Roman vial that is very bulbous in the centre and slightly at the base. Blue-green in colour with very visible iridescence in patches.

A Roman glass vial

Glass
Mid-1st Century BCE onwards
LDOSJ 5528
226mm height; 19mm rim diameter; 35mm maximum diameter; 14mm base diameter

This is a vial from a collection of nine small-sized Roman glassware vessels. This collection of glassware was gifted to the museum, although the details of when and who gifted them are unknown. This piece and the others in the collection are likely glass-blown, which is indicated by the fact that they are slightly asymmetrical and the by the presence of bubbles in the glass. This method of production indicates that these pieces were made after the middle of the 1st century BCE, when glass-blowing became the prevalent method of glass-forming. As a direct result of this development, glass became much more accessible to citizens without great wealth.  

This piece, along with the others in the collection, are low-volume holding vessels and are thus likely to have been used for more expensive liquids such as perfumes or unguents.  

The blue-green colour of this vial indicates the use of a mineral alkali (or natron) flux in the production process. Roman accounts describe this flux as originating from the Wadi Natrun in Egypt. Although the glass itself may have been produced in Egypt, due to the widespread nature of glass recycling in the Roman period, this piece may not have taken its final form here. The persistence of the blue-green colour shows that there was no effort made to the remove or change the colour of the glass through the use of additional fluxes. Thus the blue-green colour of the glass (alongside the lack of decoration) suggests that the items were not high-status. 

Although the precise provenance of the glassware is unknown, these objects were likely to have been found in a burial context due to the intact nature of the items.  

Areas of iridescence can be seen on the surface of the glass. This is the result of weathering caused by moisture. Exposure to moisture causes alkali ions to be leached and replaced with hydrogen ions from water, and the re-occurrence this process forms layers of weathering that results in refraction and thereby causes the interplay of changing colours.

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