From time immemorial, optically transparent fused silica glasses have been treasured for their physical, chemical and aesthetic qualities. When it comes to producing and patterning such glasses, the image that typically springs to mind is of a high-temperature furnace and a sweaty glass-blower skilfully moulding the molten starting material. But are such extreme working conditions and manual dexterity strictly necessary? Perhaps not. In this issue, Kotz et al. describe a method for fabricating high-quality glass components of arbitrary complexity using a standard 'stereolithographic' 3D printer (F. Kotz et al. Nature 544, 337–339; 2017).
Key to the authors' approach is the development of a fluid composite consisting of silica nanoparticles dispersed in a monomeric matrix that is polymerized during the printing process. Kotz et al. carefully chose the ingredients of this nanocomposite such that when the printed, polymerized structure is sintered — fused at temperatures of about 1,300 °C — it yields a glass of high optical quality. The glass faithfully replicates the printed edifice and has impressive thermal resistance (pictured). Its intricate features are limited only by the resolution of the printer (a few tens of micrometres in this case).