Ribbed Bowl; glass; mosaic glass; millefiori technique; glass; mosaic technique; Total: Height: 5 cm; Diameter: 13 cm; Drinking and barware; container; storage; kitchen work; Early Imperial Period; Augustus; Tiberius; Caligula; Claudius; Roman antiquity; The ribbed bowl shows a white-opaque spiral pattern in front of a dark blue translucent background. To produce it; glass rods of different colors were first placed on top of each other; heated and rolled up. Straight or diagonal panes could be cut from the resulting rod. They were placed in a hollow form; filled the spaces between them with glass mass and then fused the glass. The regular glass plates ran and led to an uneven arrangement of the spirals. The colorful effect of the glass was intended to imitate precious and semi-precious stones; glass; however; already served as a luxury good per se. In the center of the base there is a hole drilled afterwards. Allegedly; the bowl was formerly in a gold-plated copper setting of the 12th century and served as a communion cup at that time. According to Axel von Saldern; however; the hole could also have been drilled to take a material sample for chemical analysis.