Colorless glass

Colorless glass was highly prized because it resembles rock crystal.  Decolorized glass became fashionable in the third quarter of the first century and remained fashionable for fine drinking services even after the demise Roman empire.   Colorless glass was not often mold-blown because mold blown designs are difficult to see in colorless glass.  Colorless glass has always been prefered for engraved and facet-cut glass objects.