Vermilion is an opaque orangish red pigment, similar to scarlet. As a naturally occurring mineral pigment, it is known as cinnabar, and was in use around the world before the Common Era began. Most naturally produced vermilion comes from cinnabar mined in China, and vermilion is nowadays commonly called 'China red'. 'Cinnabar' and 'vermilion' were used interchangeably to describe either the natural or manufactured pigment until the 17th century when vermilion became the more common name. The chemical structure of the pigment is HgS mercuric sulfide; like most mercury compounds it is considered toxic. Vermilion is now produced by reacting mercury with molten sulfur.