Green earth
A soft, grey-green clay with almost no tinting strength, and one of the most consequential pigments in European painting — because for four centuries it was what human flesh was painted on top of.
Origin
Green earth is a natural clay coloured by the minerals glauconite and celadonite, formed on ancient sea floors and found wherever those deposits surface: Verona, Cyprus, Bohemia, the Mendip Hills. Verona green was the standard and gave the pigment its Italian name, terra verde. It requires no processing beyond washing and grinding, it is abundant, and it was correspondingly cheap. Different deposits vary considerably in warmth and saturation, from a bluish grey-green to a distinctly olive brown-green, and Renaissance treatises name them by source the way a wine list names regions.
In art history
Its central role is verdaccio, the green-grey underpainting used beneath flesh in Italian tempera and early oil painting. The logic is optical: skin tones are warm, and a cool green laid underneath and allowed to show through the thin, semi-transparent flesh layers neutralises and cools the shadows exactly where they need it, producing the subtle grey-green half-tones that make Renaissance faces look like flesh rather than paint. Giotto, Duccio and the whole Sienese and Florentine tradition worked this way, and it is visible today in unfinished panels and in works where the upper flesh layers have grown more transparent with age — which is why some fifteenth-century Madonnas now look faintly seasick. Leonardo used a verdaccio base. Green earth was also the standard green of Roman wall painting and remains common in fresco.
In the studio
It is weak, and that is its virtue. Green earth cannot overpower anything; it modulates. It is semi-transparent, dries at a moderate rate, is completely lightfast and inert, and is safe in fresco because it is unaffected by lime — one of the very few greens that is. In watercolour it granulates heavily and settles into paper texture. Its limitation is obvious: it can produce nothing bright. A landscape painted only in green earth is a landscape in fog, which is why it was always used as a base or a modifier rather than as a green in its own right.
Afterlife
Natural green earth is still mined and sold, though many modern tubes labelled terre verte are imitations built from viridian, ochre and black, which match the hue and miss the point entirely — the imitation is stronger and more opaque, and strength is precisely what the original does not have. Conservators and egg-tempera painters still buy the genuine clay.
Where it appears
Every era and artist in this atlas whose palette includes this pigment.