(mineralology) A type of quartz, often found in the hollow cavity of agate geodes, consisting of a layer of minute quartz crystals that have crystallized on the surface.

A portable electric radiant heater consisting of elements sealed in quartz glass tubes which produce infrared radiation in front of a reflective backing.

(electronics) A small crystal of quartz accurately cut in certain directions so that it can be vibrated at a particular frequency, to produce an electric signal of constant known frequency.

A mercury vapor lamp consisting of an ultraviolet light source, and enclosed by an envelope made from quartz rather than glass, which transmits ultraviolet light with little absorption.

(chemical engineering) A type of glass consisting of almost pure silica in amorphous (noncrystalline) form.

plural of quartz glass

Synonym of fused quartz

A type of light bulb consisting of a quartz bulb and a tungsten filament and the bulb containing iodine, operating at a high temperature and producing an intense light.

plural of quartz lamp

plural of quartz watch