What type of oil is commonly added to oil paints to enhance drying?

Linseed oil is the type of oil that is most commonly added to oil paints to improve their drying properties. This oil is derived from the seeds of the flax plant and contains compounds that facilitate the oxidation process, allowing the paint to dry faster than it would without any additives. Additionally, linseed oil enhances the consistency and flow of the paint, making it easier for artists to manipulate.

This characteristic makes linseed oil a favored medium in oil painting, as it allows for a more workable texture and enhances the paint's adherence to the canvas. Its drying properties are particularly important for artists who wish to layer paint in their work; the drying time must accommodate this technique without causing unintended mixing or smudging. Other types of oils, like castor oil, mineral oil, and olive oil, do not share the same beneficial drying qualities and are typically not used in the same way in oil painting.