Spotlight on Cobalt Blue


cobalt blue
Cobalt Blue is a clean blue that is neither warm nor cold. With a moderate tinting strength, it is useful on the palette for muted colour mixes. It is semi-transparent in both Winsor & Newton Artists’ Oil Colour and Artists’ Water Colour. Cobalt blue deep, a unique, red shade cobalt blue is made by using Cobalt zinc silicate. Until the nineteenth century the best blue pigment available to artists was ultramarine. Laboriously ground from lapis lazuli, a semi-precious stone mined only in distant Afghanistan, the prohibitive costs of this pigment prompted the Napoleonic administration to find an alternative. The chemist Louis-Jacques Thenard was commissioned by the French interior minister, Chaptal, himself an industrial chemist, to develop a synthetic substitute for ultramarine.

Thenard knew the famous Sevres potteries used salts containing cobalt (smalt) to produce their blue glazes, and in 1802, from a mix of cobalt salts and alumina, he produced a pigment called cobalt blue. With a purer tint than Prussian Blue, it was immediately taken up by artists. In fact, cobalt blue sometimes is called Parrish blue after the artist Maxfield Parrish who made famously intense blue skyscapes using this colour.

On a contemporary note, in 2007 Winsor & Newton celebrated 175 years of colour making and, to mark the occasion, Smalt (Dumont's Blue) watercolour was re-introduced as a limited-edition colour.

Smalt is a bright variation on cobalt blue, made from the ground pigment of cobalt glass used in classical stained glass and pottery where a cobalt compound would be included in a glass melt. Now, in 2019, we are thrilled to be re-launching this special blue colour as a permanent part of our range.