This blown glass bottle is transparent with pale green shades. The patina adds a beautiful iridescent polychromy in places, the intensity of which depends on the light.
After blowing a single parison, the glassmaker created the two compartments by pinching the glass vertically, so as to form an inner wall: in our example, the two elements seem to be totally separated, while other specimens may contain two similar tubes that communicate at the bottom, by means of a channel. The handles, modeled in glass ribbons of the same color, were made separately: they served to suspend the vessel from a string. The lid, which would have been made of a perishable material (wax, cork, fabric, etc.), is never preserved.
These double-tube flasks are the elaborate and later version (from the 4th century A.D. onwards) of the elongated, cylindrical cosmetic vessels that were very popular from the 1st century: they were intended to store kohl, a black powder used as eye makeup and probably applied, as it is today, on the edge of the eyelids. Already documented in the 3rd millennium B.C., kohl also served as a protection against eye ailments related to the arid or semi-arid climate of the desert.
Such containers exist in many versions (double balsam jars would have contained a substance of two different colors) and were often excavated with small sticks provided with a bulbous end, which were used to take the kohl from the tube and apply it on the eyes: some were made of glass, while the more luxurious examples were made of bronze or carved from bone.