Fine glass is the latest material to be manufactured additively. Glassmaking began 4,500 years ago, in Mesopotamia. The industry’s first products were trinkets, such as beads and pendants, cast from moulds and carved by hand. But craftsmen quickly worked out how to make more practical stuff, such as jugs, bottles and drinking vessels, by coiling strands of molten glass around a sand or clay core of appropriate shape, which could then be shaken or scraped out after the glass had cooled.
Since those early days, many other ways of forming glass have been invented. These range from blowing forcefully through a tube to inflate a hot gob of the stuff, creating a hollow vessel, to floating it as a liquid on a bed of molten tin to produce perfectly flat window panes. But ancient wisdom often still has value, and now a group of researchers at the Massachusetts Institute of Technology have had another look at the coiling method, pronounced it good, and modernised it. Their principal updating is to dispense with the core. Instead, they have turned to the field of 3D printing—or additive manufacturing, to give its formal name. Objects of rare beauty, and possibly of great utility, result.