Glass inlays were created using a selection of metal oxides to colour the glass. The glass makers were diligent and precise in their use of oxides, in order to ensure that the correct colours and shades were achieved. Archaeological evidence suggests that glass making, prior to the evolution of glass-blowing techniques, was mostly monopolised by the social elite.
Glass bar inlays such as these were formed from two differing coloured rods fused together, and then cut to create the desired shape and length. Whilst these rods are relatively simple in nature, more complicated patterns included the addition of feathering, facial elements or floral motifs.