This enigmatic object finds its closest parallel in a barrel-shaped bottle of colorless glass now in Cologne, no. 54 in Harden, Glass of the Caesars. The bottle in Cologne is of the same shape, also with spiral trailing on each end, but not, as here, tooled into a festoon pattern. It differs from the present example in that it is an open bottle rather than a sealed container; it has four small feet and a short central spout with loop handles. When this container was presented at auction in 1990, a Hellenistic date was suggested, but the style of the trailing seems to indicate a Roman date.
Ancient vessels still containing their original contents are exceedingly rare. A Hellenistic core-formed amphoriskos preserved its contents through the accidental formation of a weathering layer that formed a protective seal. The viscous brown liquid contained therein had an olive oil base, and most likely was perfume. For the Hellenistic amphoriskos, and a short list of other vessels, all Roman in date, that still contain their original contents, see p. 28 and note 15 in Auth, "The Eugene Schaefer Collection of Ancient Glass at the Newark Museum: A New Look at an Old Collection" in Annales du 6e Congrès de L'Association Internationale pour L'Histoire du Verre.