Quartz solid solution glass ceramics and precursors thereof are described, which are characterized by very good mechanical and optical properties and can be used in particular as restorative materials in dentistry.

Additive manufacturing processes for making transparent three-dimensional parts from inorganic material powders involve selective use of vacuum to remove or avoid trapped bubbles in the parts.

A device for manufacturing SiO.sub.2TiO.sub.2 based glass by growing a glass ingot upon a target by a direct method. The device includes the target, comprising a thermal storage portion that accumulates heat by being preheated, and a heat insulating portion that suppresses conduction of heat from the thermal storage portion in a direction opposite to the glass ingot.