Ver aquí: he three centuries in which the surviving painting remained trapped within a tight space behind the altar table, inevitably led to the surface accumulation of a considerable amount of dirt, which easily settled on the naturally harsh surface of the intonaco as well as the various damaged areas provoked by the 16th century changes. Conditions were further aggravated by rainwater infiltrations, originating from the overhead window, which ran down and stagnated on the painting. Masaccio's painting today, in fact, reveals the consequences of this event (especially in the overall surface abrasion, the weakened pictorial film and instability of a few pigments) in addition to other similar though less easily explained phenomena.

(...) If the cleaning proved summary, the consolidation of the pictorial film was, instead, most consistent and carried out with egg and oil based substances.
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