Amorphous carbonia, also called a-carbonia or a-CO2, is an exotic amorphous solid form of carbon dioxide that is analogous to amorphous silica glass. It was first made in the laboratory in 2006 by subjecting dry ice to high pressures (40-48 gigapascal, or 400,000 to 480,000 atmospheres), in a diamond anvil cell. Amorphous carbonia is not stable at ordinary pressures—it quickly reverts to normal CO2. Mixtures of a-carbonia and a-silica may be a prospective very hard and stiff glass material stable at room temperature. Such glass may serve as protective coatings, e.g. in microelectronics.