AMBER VARNISH
MANY painters believe that, owing to the fact that Amber is the hardest resin there is, the varnish made from it should retain its gloss the longest, and be just as free from cracking and bloom as the natural resin itself.
An examination of several of the amber varnishes on the market reveals the fact that there probably is no such varnish made. Although Amber can be fused and melted, it takes such a high heat that even the lightest gum Amber becomes exceedingly dark and then it must be diluted with so much oil that there is very little gum Amber in the varnish itself. Most of the Amber Varnishes on the market are Copal Varnishes that contain little or no Amber at all.
It is very wise for the painter to keep away from materials of this type; and, if a hard drying varnish is desired, any good Copal Varnish will answer the purpose, although for varnishing pictures, it must be continually borne in mind that a simple varnish like Damar, Mastic or Sandarac should be used; for only those simple varnishes can be easily removed without destroying the painting itself.