Glastechnische Berichte

absorption activation addition agent analyses ancient glass antimony appears base bien birefringence century chemical color composition concentration conductivity containing crater crystal d'une dans le determined deux diffusion DISCUSSION du verre effect electric electron elements été evidence examined example experiments fabrication fait Figure four fracture furnace Glas Gläser glassmaking heat important included increase indicate industry International ions iron Italy Jahrhundert known Laboratories lead manganese mark material measurements melting metallic meteorite methods nature objects observed obtained oxide period phase possible premier present probably problem production qu'il question reported Roman samples separation shown shows siècle silica silicate glasses similar specimens structure suggests surface Table tank technique temperature tion trouvé University values verre