Diversité et évolution du vitrage de l’Antiquité et du haut Moyen Âge : un état de la question

Abstract

Abstract. Archaeological finds, literary sources and to a lesser extent iconography allow to define different kinds of window glass and lapis specularis. From the the vast documentation gathered from the Western world, it is possible to distinguish an evolution in the forms, techniques and material used fom the 6th to the 7th century; the study attempts to find out and underline the place of window glass in architecture. The poured and flattened glass, as soon as the Augustan period, is part of the equipment of public and wealthy residential buildings, cult places and especially thermal complexes. The most numerous, flat and orthogonal, are known from a long time. Others, circular or rectangular but balloon shape are mostly used for zenithal lighting. Blown window glass appears during the fourth century. In the Western world, window glass is only obtained by cylinder glass blowing, but in the Eastern provinces, cylinder glass panes and glass discs produced by crown blowing are used together. As soon as the 4th century, glass panels are cut in small geometric stained figures, which will give birth to stained-glass being coloured during the 6th century; the first painted stained-glass appears in the 8th century. Records of lapis specularis in literary sources are more substantial than archaeological data; its transparency often is of higher quality than glass. This material, extracted from successive exploited fields is being used all along the considered period.