gold size

gold size (countable and uncountable, plural gold sizes)

1. (art) A size (or viscous wash) put down on a surface on which gold leaf is to be applied. [from 17th c.]
   • 1735, Dictionarium Polygraphicum, volume I:

     Whatsoever you would gild must be first drawn with a gold size.

   • 1842, William Thomas Brande, A Dictionary of Science, Literature and Art:

     Gold size […] is drying oil mixed with calcined red ochre.

• goldsize