Quartz Infrared Heater

infrared heater
A source of heat-producing wavelengths, longer than visible light, which do not heat the air through which they pass, but only those objects in the line of sight.
An infrared heater is a body with a higher temperature which transfers energy to a body with a lower temperature through electromagnetic radiation. Depending on the temperature of the emitting body, the wavelength of the infrared radiation ranges from 780 nm to 1 mm.
An infrared or radiant furnace is one that uses infrared lamps, electric heating elements, flames, or radiant tubes to heat the product.  Although the heaters may also heat the furnace gasses, the primary heat source is radiant heating.  See Infrared Heaters below.

quartz
quartz glass: colorless glass made of almost pure silica
a hard glossy mineral consisting of silicon dioxide in crystal form; present in most rocks (especially sandstone and granite); yellow sand is quartz with iron oxide impurities
Quartz is the second most abundant mineral in the Earth's continental crust, after feldspar. It is made up of a continuous framework of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall formula SiO2.
A hard white or colorless mineral consisting of silicon dioxide, found widely in igneous, metamorphic, and sedimentary rocks. It is often colored by impurities (as in amethyst, citrine, and cairngorm)