The research on manuscripts provides useful information about the artistic/technical production and scientific development in the past. However, the reproduction of ancient recipes is difficult because most are described generally, or they hide essential information to preserve production secrets. In this study, four different recipes from the medieval Manuscript H-490 (Ecole de Medicine of Montpellier University) were reproduced. The raw materials and the production process of each recipe were discussed from teh point of view of glassmaking, and the final products were characterised. The recipe indicated the preparation of a white glaze, similar to Islamic frits. Other recipes explained the preparation of an "unbreakable" glass; however, the characterisation of the final products showed that no changes in the hardness of the glass were obtained. Another recipe described the preparation of a green glass which was successfully obtained.
