Gamblin Gamvar Picture Varnish 5.4 oz.: Gamvar is a low molecular weight synthetic resin varnish developed by conservation scientists at the National Gallery. It looks as good as damar natural resin varnish, but never yellows. Like damar it has a high shine and will saturate the colors of paintings and intensify the transparency of glazes. Gamvar is easy to remove with mild solvents. The 5.4 oz. package (of ready to prepare solvent and resin chunks) covers up to 10 square feet of oil or acrylic paintings and can also be used for retouch.