Abstract
A total of 1496 investigated colourless glassanalyses have been collected with the aim of achievinga clear geographical, typological, chronological andcompositional overview on this particular type of glass.Based on manganese and antimony contents, four maingroups were characterised: naturally colourless, Mn-decoloured, Sb-decoloured and Mn/Sb-decoloured.Main achievements relates to the chronological distribu-tion of manganese and antimony technologies, the for-mer being associated to a long lasting technology whichculminated during the Late Antique period while thelatter being practically absent after the 8th
century AD, being at its acme during the Roman imperial period.Except for naturally colourless glass, glass-making tech-nology mostly implied the use of impure sands and na-tron, relegating the other components to a virtually irrel-evant presence, except during the Late Antique andMedieval periods