Antické sklo ze sbírky Národního muzea tvarované pomocí formy a foukané do formy / Sagged and mold-blown ancient glass from the collection of the National Museum, Prague
By the close of the Hellenistic era new class of tableware appeared: so called grooved bowls made by sagging over or through hemispherical or conical former mold. Prominent form of vessels became bowls with ribs on its sides, so called ribbed bowls. They were made from monochrome and mosaic glass. Toward the end of first century B. C. was invented blowing pipe and soon after free blowing began blowing into a mold. Multiple copies with decoration were made especially in the first century A.D.