Linseed Oil, varnish oil

Refined linseed oil is a pale yellow medium—extracted using high pressure and heat—that is commonly used in the production of economical oil paints. It dries to a tough, durable film, but artists should be mindful of how it ages over time. Although it begins much lighter in color than cold-pressed oil, it eventually yellows to the exact same degree. Because of this initially pale starting point, the long-term color shift can actually appear much more dramatic.