Diatom. Photo by Pascal Jean Lopez / CNRS
Research concerning the origins of glass typically treats the material as a human-made substance, discovered by melting sand and other minerals beyond a certain temperature. The ensuing trajectory of glass has been a fascinating one, from Egyptian glass beads formed in 2500 BC to the expansive curtains of glass that envelop modern buildings today. Despite the significant changes glass has seen throughout its history, however, its manufacturing has largely remained the same—at least in terms of embodied energy. To this day, glass still requires hot ovens to achieve the target melting point of silica.
Enter the diatom. This humble and practically ubiquitous form of marine algae is responsible for 25% of our oxygen, and as scientists from the French National Centre for Scientific Research have reminded us—has a glass skeleton. As it grows, the diatom absorbs silicon atoms present in ocean water and assembles them into sophisticated glass structures. The diatom not only dispels the myth that glass is a human invention, but also demonstrates that glass does not require embodied energy for its fabrication. For now, researchers are attempting to emulate this assembly method in various nanotechnological applications. Thanks to this simple building block of life, perhaps we will one day be able to utilize oven-free glass at the scale of buildings.