Carbonate-containing salts are industrially and minerologically ubiquitous. The term "carbonate" is also commonly used to refer to one of these salts. Most common is limestone, or calcium carbonate.
The term is also used as a verb, to describe the process of raising carbonate and bicarbonate concentrations in water, see also carbonated water, either by the introduction under pressure of carbon dioxide gas into the water, or by dissoving carbonate or bicarbonate salts into the water.
At one time, it was thought that the presence of carbonates in rock was unequivocal evidence for the presence of liquid water. Recent observations of two planetary nebulae reported in the January 17, 2002 issue of the scientific journal Nature indicate that carbonates can form in interplanetary space.