This painting’s only problem was that it was covered by an extremely discolored varnish. Varnishes are traditionally applied to finished paintings to provide for an even saturated surface as well as a provide a protection for the paintfilm. Traditional varnishes were made from natural resins such as Dammar and Mastic and their slightly yellow hue provided a sense of warmth to the painting. Unfortunately, with time these resins darken considerably and turn opaque. Within the past 50 years many new synthetic reins have been introduced which are being used as picture varnishes. Although the new varnishes offer the great advantages of little discoloration and easy removability, they can fail to provide the warm saturation and pleasing appearance of Dammar or Mastic.
Removing varnish from a painting is a delicate procedure. Organic solvents are employed and testing must be done to determine the proper solvents to be used. Often several different solvents or solvent mixtures will be used on a particular painting because of the the different sensitivities of different colors. Usually it is desirable to leave a little old varnish on the painting to assure that the original paint film is left intact.