Damar Crystals are made from the resin of a Southeast Asian pine tree. They are commonly used to make varnishes for the last layer of painting, but also are sometimes added to mediums for glaze effects.
A varnish concentrate for coating paintings can be made with roughly equal amounts of Damar concentrate and Oil of Spike Lavender. A re-touch varnish can be made by adding more Oil of Spike Lavender. Keep in mind that Oil of Spike Lavender is strong – do not “scrub” the painting with it. The goal is for it to evaporate, leaving the Damar film.