A theoretical reconstruction of ancient manufacturing methods depends on a correct interpretation of the extant manufacturing traces. An error with serious consequences was the misinterpretation of the typical scratches of ancient glass as grinding marks. Generations of archaeologists were convinced that especially Roman glassworkers had a superior command of the art of glass cutting and grinding, which supposedly was never again surpassed in history. A few years ago, a new interpretation of the typical scratches of ancient glass was given, explaining the scratches as traces of the hot melting process. Recent scientific investigations support this new perception. A summarizing presentation of the topic is given in this paper to provide a realistic starting point for further research about the ancient glass manufacturing methods.
