In what kind of painting are pigments suspended in water applied to a damp lime-plaster surface and was traditionally seen directly painted onto walls?

Fresco (Buon fresco technique)

Explanation:

Fresco (Buon fresco technique) is an antiquity painting method of which pigment suspended in alkaline limewater is used on a damp lime plaster surface.

Fresco is different from limewash or a patina coat that is used on dry plaster. These method is known to be Secco.

Buon fresco technique is only applied on pure lime plaster, and must be used or done while the plaster is still damp. It is not used on a cement, or lime with cement (often known to as lime stucco) and it's impossible to be used on plaster after it is dry.

At the curing phase following application onto the wet plaster, pigmented limewater will carbonate with the plaster, and the pigment changes to be an integral portion of the lime plaster surface. Fresco it's employed on interior or exterior lime plaster.

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