cinnabar (sĭnˈəbär) [key], mineral, the sulfide of mercury, HgS. Deep red in color, it is used as a pigment (see vermilion), but principally it is a source of the metal mercury. It is mined in Spain, Italy, and in the United States in California. The mercury is obtained from it by roasting, the sulfur combining with oxygen and passing off as sulfur dioxide.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.