Frieze of Angels, detail of cleaning test

Inherent causes of deterioration

The physical and chemical make-up of a work of art can contribute to its own deterioration. Artists may choose materials for aesthetic reasons, inadvertently selecting unstable materials. In some of his murals, Sargent used paint containing an inadequate amount of binding medium to achieve a matte visual effect. This type of under-bound paint is vulnerable to pollutants in the atmosphere and susceptible to physical damage, such as abrasion.
Frieze of Angels, detail of cleaning test with
a cotton swab. The red pigment is sensitive
to the mildest of solvents because it is under-bound,
making cleaning difficult. (1999 photo)
The Triumph of Religion