The glass 3D printing technology is advancing.

MICRON3DP’s glass 3D printer is based on an FFF (fused filament fabrication) technique which operates at much higher temperatures than its plastic 3D printer counterpart. 

Achieving a fine resolution for glass 3D printing had been a distinct challenge for the Israeli glass printing company. (…) The company seems to have broken ground on this front and will be introducing a high-resolution glass 3D printer, capable of layer thicknesses of as little as 100 microns. With a respectable build volume of 200 x 200 x 200 mm. (…) Because the technology utilizes molten glass, little post-processing would be needed once the print is complete.