Synthetic pigment

History

The first known synthetic pigment was Egyptian blue, which is first attested on an alabaster bowl in Egypt dated to Naqada III (circa 3250 BC). Egyptian blue (blue frit), is calcium copper silicate CaCuSi₄O₁₀, made by heating a mixture of quartz sand, lime, a flux and a copper source, such as malachite. Already invented in the Predynastic Period of Egypt, its use became widespread by the 4th Dynasty. It was the blue pigment par excellence of Roman antiquity; its art technological traces vanished in the course of the Middle Ages until its rediscovery in the context of the Egyptian campaign and the excavations in Pompeii and Herculaneum. Later premodern synthetic pigments include white lead (basic lead carbonate, (PbCO₃)₂Pb(OH)₂), vermilion, verdigris, and lead-tin yellow. Vermilion, a mercurysulfide, was originally made by grinding a powder of natural cinnabar. From the 17th century on, it was also synthesized from the elements. It was favored by old masters such as Titian. Indian yellow was once produced by collecting the urine of cattle that had been fed only mango leaves. Dutch and Flemish painters of the 17th and 18th centuries favored it for its luminescent qualities, and often used it to represent sunlight. Since mango leaves are nutritionally inadequate for cattle, the practice of harvesting Indian yellow was eventually declared to be inhumane. Modern hues of Indian yellow are made from synthetic pigments. Vermillion has been partially replaced in by cadmium reds.