Stil de grain
Composition and Properties of Stil de Grain
Stil de grain pigment is derived from buckthorn berries (Rhamnus cathartica). The main coloring component according to the most recent research (1) is the quercitrin, a glycoside formed from the flavonoid quercetin and the sugar rhamnose. Older sources name rhamnetin and rhamnazin as coloring components as well. The pigment is fugitive and not lightfast.
Names
Yellow lake, Buckthorn lake, Dutch yellow, Persian lake, yellow madder, pinke yellowNY 14, CI 75440French name of the pigment
Preparation
According to Bersch (1), the lake is prepared by boiling the crushed berries with water and mixing the extract with a solution of alum [hydrated potassium aluminum sulfate KAl(SO4)2·12H2O].“The lake is then precipitated by the addition of powdered chalk. As a rule, 500 parts of water are used to 100 parts of berries, 20 parts of alum are added to the decoction, and the mixture poured upon 75 parts of finely powdered chalk.”Another recipe describes the plant berries as being steeped in lye (potash or potassium carbonate K2CO3), then precipitated with alum to create a translucent yellow lake pigment. Different hues can be attained by the addition of tin, copper or iron salts. The temperature also has an effect on the resulting color: a lemon yellow lake is obtained up to 50° C, and a darker, orange-colored lake is obtained at 100° C.Ripe buckthorn berries. Image: Iris Männig
History of Use
The pigment was in use since the medieval times and was popular with baroque painters such as Vermeer, Rubens, and Rembrandt. The description of the history of stil de grain at Natural Pigments quotes from old sources such asPiles, Roger de, Jombert, Charles Antoine [Ed.] Élémens de peinture pratique — Amsterdam & Leipsick, 1776Osborne, Laughton, Handbook of Young Artists and Amateurs in Oilpainting: Being chiefly a condensed compilation from the celebrated manual of Bouvier, with additional matter selected from the labors of Merimée, de Montabert and other distinguished continental writers in the art in seven parts. New York: J. Wiley, 1849, p. 53.Both books are available in digitized facsimile form (see links given above).Example of use
