Green earth, also known as terre verte and Verona green, is an inorganic pigment derived from the minerals celadonite and glauconite. Its chemical formula is K[(Al,FeIII),(FeII,Mg](AlSi3,Si4)O10(OH)2.
First used by the ancient Romans, green earth has been identified on wall paintings at Pompeii and Dura-Europos. The Renaissance painter and writer Cennino Cennini claimed that “the ancients never gilded except with this green” being used as a bole, or undercoating. In the Middle Ages one of its best-known uses was in the underpainting of flesh tones.
High quality deposits can be found in England, France, Cyprus, Germany and at Monte Baldo near Verona in Italy. The color ranges from neutral yellow green to pale greenish gray to dark matte olive green.