Examples of stratigraphic investigation of historic plaster revealing an earlier fresco decoration (a), and of a canvas painting revealing earlier versions of drapery (b)
Stratigraphic investigation is sometimes an essential part of the examination undertaken before conservation treatment. Small, defined test areas are selected on an architectural surface, sculpture or painting, and more recent layers are progressively removed to identify evidence of older decorative schemes.
Stratigraphic investigation helps
to deepen our understanding of the work. The findings can guide conservation decisions and inform further scientific examination, such as identifying a pigment and dating its use to help establish the age of a newly revealed layer.
