Linseed oil is an essential oil for the traditional decorative painter who uses an oil glaze.
Linseed (or Flax) is a sicative oil – meaning it will eventually dry. Walnut and poppy oil also fall into this category. Most other oils like olive, peanut, etc. will never dry, and therefore, they are not useful for painting.
History: Prior to the discovery of the sicative oils, fine art painting mediums consisted mostly of distemper (early whitewash paint) and casein. The discovery of sicative oils in fine art painting is generally attributed to the 15th century Netherlandish painter, Jan van Eyck. This discovery, which was held secret for as long as possible, allowed artists to blend and work in transparent layers (as seen in this “Arnolfini Wedding” by Van Eyck). This completely transformed the way easel painting was done.
Uses in decorative painting: Up until the 20th century, when water-borne material took favor, oil glaze was the standard medium for decorative painting. Woodgraining, faux marble, trompe l’oeil, murals, and glazing techniques were all achieved using an oil glaze. Linseed oil may take up to 3 months to dry by itself, so it must be mixed with a solvent (TURPENTINE). Additionally, I add Japan drier a more speedy dry time. See my OIL GLAZE RECIPE.
When choosing a linseed oil for decorative painting, I recommend only “cold-pressed, refined (clarified) linseed oil.” Boiled linseed oil is not the quality I would ever choose for my oil glaze. I purchase the clearest oil I can find. If the oil does NOT come in a clear container, you can bet that it is very yellow to begin with. So, I buy linseed oil from an artist supply store in a clear, plastic container. I place it immediately on the windowsill of my shop so it becomes naturally sun-bleached. (Note the lighter linseed in the back.)
When glazing, you should know that the dried glaze will yellow for a few weeks (this yellowing varies on it’s clarity). After that, as long as the glazed area is hit by sunlight, the yellowing effect should dissipate – but there is always a hint of yellowing with an oil glaze.