These stunning pieces show their original translucency: 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.
Many items of ancient glassware were designed for tableware use, in particular for carrying and serving water and wine at banquets. Bottles were one of the most frequently used containers, and existed in different dimensions and shapes. This variety was allowed by the technique of glass-blowing, which had revolutionised the art of glass-making by the first century AD.