PG23—Green Earth
Pigment Type
earth
Chemical Name
hydrated iron, magnesium, aluminum and potassium silicates
Chemical Formula
K[(Al,FeIII),(FeII,Mg)](AlSi3,Si4)O10(OH)2
Properties
Green earth is a natural pigment that varies from yellow and olive to blue-green in its composition and hues. It is semi-transparent, has low hiding power and tinting strength, muddies and darkens in oil, and is particularly good for tempera and fresco painting.
Permanence
Green Earth has excellent permanence and lightfastness, although some varieties can be developed by light calcining. It is one of the most permanent pigments because Earths are not affected by sunlight or atmospheric conditions.
Toxicity
Green Earth has no significant hazards.
History
Terre verte is French for green earth. It was discovered in antiquity, and its use has been traced to the Ajanta caves in India and a variety of Roman sites, including Pompeii. Green Earth was very popular for underpainting flesh tones in medieval paintings because this green was the compliment to pink on the medieval color wheel. Its use declined after the Renaissance. The natural supplies of the pigment are mostly depleted, and manufacturers currently duplicate the hue using mineral bases like Viridian, iron oxide, or chromium oxide, or artificial ceramic colorants. Pigments sold under this name can also be the result of mixing Sienna and Phthalo Green.
Alternate Names
Celadon Green, Celadonite. Green Bice, Holly Green, Stone Green, Terra Verte, Verdeterra, Verdetta, Veronese Green. Bohemian Earth is a high quality, clear, middle-green variety. Cyprus Green Earth, or Cyprian, is a high quality yellowish variety. Tyrolean and Verona Earth are high quality bluish varieties. Verona Brown is a calcinated variation of Green Earth. Burnt Green Earth is similar to Transparent Brown
