After the mid-fourth century, glassmaking declined in the Roman Empire. In the east, where the decline was less pronounced, a group of deep blue flasks, pitchers, and lamps with coiled bases was produced. They seem to have been made in a single workshop, but examples have been found as far afield as the Sudan and South Korea. One member of the group is this head flask, which was blown in a two-part mold. The handle was applied to the neck, drawn out and down, and attached to the head. The remaining glass was dragged down to the neck and notched. The thumb-rest at the apex of the handle was made by pinching the hot glass with pincers. Only three other head flasks made from the same mold are known to exist. The Corning flask once belonged to the celebrated operatic tenor Enrico Caruso.