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. Cobalt Blue is a clean blue pigment. It was discovered in 1802 by French chemist Louis Thenard as an alternative pigment to the expensive Lapis Lazuli blue pigment. 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.