Spotlight on Ultramarine
The word ‘Ultramarine’ comes from the Latin ‘ultra’ meaning ‘beyond’ and ‘mare’ meaning ‘sea’, as this was how Lapis Lazuli first arrived in Europe. Ultramarine came in the form of lumps of the semi-precious stone Lapis Lazuli (the ‘blue stone’ in Latin), via foot and donkey on the Silk Road from Afghanistan, and was then was loaded onto ships in Syria sailing to Venice where it was traded throughout other parts of Europe. One of the oldest blue pigments, early evidence of Ultramarine’s use can be found in Afghanistan in the Temples of Bamiyan in 6-7th c AD.
Lapis Lazuli is a mix of minerals Lazurite, Silicate and Pyrite and while this mined stone was used for decoration purposes in Ancient Egypt and Sumeria, the blue pigment was not extracted until much later, with evidence of this used in Chinese paintings from the 10th and 11th centuries, in Indian mural paintings from the 11th, 12th, and 17th centuries, and Anglo-Saxon and Norman illuminated manuscripts from c.1100. In the 15th century, the artist Cennino Cennini describes Ultramarine in his Il Libro dell'Arte, as a “...glorious, lovely and absolutely perfect pigment beyond all the pigments”.
However, to produce genuine Ultramarine pigment from Lapis Lazuli a complex and time-consuming process is needed. Following the mineral being mined and transported, it is then ground and mixed with resin, linseed oil (or wax), and then heated to form a dough-like mixture, which would then be kneaded like bread, and placed in a lye solution allowing for blue flakes to separate, sink and dry; finally resulting in a fine blue powder pigment. The process would then be repeated to produce a finer grade of pigment on each repetition; meaning that a comparative small amount of Ultramarine pigment could be extracted from the Lapis Lazuli.
Nonetheless, the intensive extraction process created a high-quality blue pigment free from the invisible impurities which lay in the rock and damaged the paint colour. The time taken, along with the distances travelled from the East, made natural Ultramarine a very expensive pigment which was once considered gram-per-gram more precious than gold.
The preciousness of the pigment dictated how it was used in painting. Artists used this pigment sparingly and had to account for the cost of this pigment which was sold at its best quality and price in Venice.
From 1400, Ultramarine was often used in paintings of the Virgin Mary for the colour of her robes to illustrate her divinity.
Ultramarine remained an expensive pigment until a synthetic Ultramarine was invented in 1828. In 1817 the Royal College of Art in England offered a prize to whoever could produce a synthetic version of Ultramarine. This was then taken up by the French Government’s Societé pour l'Encouragement d'Industrie to offer a larger reward of 6000 Francs, and in 1828 the French chemist Jean-Baptiste Guimet successfully created the first synthetic Ultramarine blue: French Ultramarine. Made from a mix of clay, soda, charcoal, quartz and sulphur heated to produce a green Ultramarine substance which is then ground washed and re-heated to convert it to the blue pigment named French Ultramarine was chemically identical to the prohibitively expensive Ultramarine pigment it derives its name from.
J. M. W. Turner was the first accredited artist to use synthetic ultramarine in 1834. More recently in 1957 the artist Yves Klein developed a version of this colour called IKB (International Klein Blue) which he registered as a trademark colour and made 200 monochrome paintings from.
Winsor & Newton, produces a French Ultramarine and a cooler Ultramarine (Green Shade).