Stil de grain yellow or sap green is a pigment derived from berries of the buckthorn species Rhamnus saxatilis, which are commonly called Avignon berries or Persian berries after two historical areas of supply; latterly Italy was a major source. The color, whose principal chemical component is rhamnetin, was formerly called pink (or pinke); latterly, to distinguish it from light red "pink", the yellow "pink" wasqualified as Dutch pink, brown pink,English pink, Italian pink, or French pink — the first three also applied to similar quercitron dyes from the American eastern black oak, Quercus velutina. Other names are Persian berries lake, yellow berries and buckthorn berries.