Lawrence Livermore National Laboratory’s Tailored Glass by DIW enables 3D printing of silica-based glass with gradient mechanical and optical properties in unlimited, customized, structural forms of high complexity. By controlling the concentration of multiple specially formulated glass inks throughout the extrusion process, the resulting glass product benefits from the free-form capabilities of 3D printing — while allowing for continuous changes in refractive index or other material properties. Following extrusion, a series of heat treatments solidifies the glass structure with the desired material or optical properties in addition to achieving high density and a range of geometries. This technology is applicable to research, consumer, and industrial markets seeking to harness tailored glass structures through rapid prototyping capabilities that cut down on the time and cost of conventional methods. This reduces expenses for customers seeking low-volume glass manufacturing. Given design flexibility and manufacturing precision, products ranging from laser system components to microfluidics can be tested and brought to market in a fraction of the time with, potentially, reduced energy requirements and less material waste.