Glass molded by a 3-D printer has been around for a few years, but never before has it looked this good. Massachusetts Institute of Technology engineers and materials experts have created a printer that spits out transparent glass, layering the glass like glue from a hot glue gun (if it was 1900°F glue).

As The Economist notes, the M.I.T. researchers had to wrestle with several iterations of glass printer: they finally developed a ceramic nozzle that could evenly pour molten glass, leading to more uniform, and ultimately stronger, structures.

Photos via Vimeo/MIT