Most of the fresco method is actually preparation. Fresco is only one type of mural painting. In most painting techniques, the artist saturates pigments with oil to make them rich, dark, and glossy.
Lime plaster can take a year to fully harden.
When colors in a fresco dry, they are lighter than when they are applied and continue to soften over time. Salts from seepage in a building can destroy frescoes. The resulting chemical reaction may produce temperatures of up to 400 degrees Fahrenheit, depending on the volume of the mixture.