Lead White Heightening
A liquid opaque white made from white lead was also commonly used in the Renaissance to add highlights to drawings in metalpoint, black or red chalk, or pen and ink. It was usually applied with a fine brush in a hatched pattern or with a broader one for a more painterly effect. It was often diluted to make a transparent white wash, and artists could produce complex effects with overlapping layers of transparent and opaque washes. Lead white is also the basis of bodycolor or gouache, when watercolor or pigment is added to it.

When used in drawing or in watercolor without the protection of varnish, lead white oxidizes and turns dark, as in this drawing by Luti. This is a common phenomenon, which can often be reversed through conservation treatment.

The terms "white heightening" or "heightening" also sometimes refer to white chalk highlights.
 


Benedetto Luti. The Assumption of the Magdalen. Private Collection, New York

 

by Michael Miller
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