“Brilliance” in your color refers to its chromatic intensity – fresh from the tube and how it looks a few years later, within your painting. “Intensity” is the result of a few simple areas of concern: the oil, the amount of pigment, and the care in preparation.
Let’s start with the oil.
A crucial part of the idea of brilliance; oil must be capable of providing clarity, accepting large amounts of pigment, and resistance to yellowing while drying to a strong, flexible film. There is one oil with such attributes and a long history of use, enabling us to see the result after 400 years of aging – Walnut Oil. Walnut Oil is a pale, free flowing oil with a unique refractive index and great resistance to yellowing. When allowed to dry with normal indoor illumination, a painting executed with colors ground in Walnut Oil will actually dry brighter and more brilliantly. Also, due to its fluid nature, Walnut Oil allows more pigment to be dispersed, compared to other oils, such as linseed oil. The additional amount of pigment produces brighter yellows and reds, and more intense blues and other darker colors. In tinting strength tests, our color ground in Walnut Oil exceeds the strength of other brands. Walnut Oil simply accepts more pigment and the resulting color is more intense.
However, the oil does not do all of this alone. Careful and precise milling must incorporate the pigment into the oil without the addition of artificial thickeners to maximize the strength and color of the pigment. The milling achieves this by “shear” force, which separates the pigment particles and surrounds each with an envelope of oil without damaging the pigment. Too much force and yellows turn green, too little force and the paint paste looks like sandpaper.
This time consuming process can sometimes take an entire day to produce 650 tubes of color. The resulting increase in smoothness, tinting strength of the color, and – above all – the brilliance, depth, and richness of the color makes it all worthwhile.
*Photo of Madonna and Child by Lorenzo di Credi, painted with Walnut Oil from the National Gallery UK website