Winsor & Newton Artists Oil Color is unmatched for its purity, quality and reliability - a success which is reflected in its world-wide reputation amongst professional artists. Every Winsor & Newton Artists Oil Color is individually formulated to enhance each pigments natural characteristics and ensure stability of color. By exercising maximum quality control throughout all stages of manufacture, selecting the most suitable drying oils and method of pigment dispersion, the unique individual properties of each color are preserved. Ultramarine Violet is a rich purple color. It is a derivation of French Ultramarine, a synthetic pigment created in 1828 by French chemist Guimet as an alternative to genuine Ultramarine. 25oz/37ml tube of Winsor & Newton Artists Oil Color Conforms to ASTM D4236 Item Dimensions: 0. 98" L x 1. 54" W x 4. 17" H.