Lead white
Lead white is the most important pigment in the history of European painting, and the one that killed the most people who made it. For two thousand years there was no serious alternative, and every white in this database before the nineteenth century is this one.
Origin
It was manufactured by the stack process, essentially unchanged from Theophrastus' description in the fourth century BCE to the industrial era. Coils of lead were placed in earthenware pots above a pool of vinegar, the pots stacked in a shed and buried in horse dung or spent tanbark. The dung fermented, giving off heat and carbon dioxide; the acetic acid vapour corroded the lead; over three months a white crust of basic lead carbonate formed on the metal, which was then knocked off, washed and ground. The Dutch made the finest grade — hence "Dutch stack process" — and the best of it, later marketed as Cremnitz white, was prized for a density and warmth that no substitute has matched. The workers who scraped the pots inhaled the dust and developed the tremors, colic and paralysis of lead poisoning. This was known and documented for centuries before anything was done about it.
In art history
Because lead white was cheap, opaque and available everywhere, it did not merely provide highlights — it formed the physical substrate of the picture. Nearly every painting from Van Eyck to Manet is built on a lead white ground, and lead white is mixed into the majority of the paint above it. It is the reason X-radiographs of paintings work at all: lead is dense enough to block X-rays, so the buried lead white underdrawing and its revisions show up as a ghost image, which is how we know what Rembrandt painted out. Vermeer's pearls are lead white impasto dots. The luminosity of Dutch interiors comes from a lead white ground glowing up through thin coloured glazes. In this collection lead white appears in twenty separate eras, more than any other single material — the most transversal pigment in the whole of Western painting.
In the studio
The reason painters resisted every substitute for so long is that lead white is not just a colour but a binding medium in disguise. It reacts with linseed oil to form lead soaps, producing a paint film that is flexible, tough and fast-drying — a lead white passage is touch-dry in days where other whites take weeks. It handles with a buttery drag that holds a brushmark or a knife edge. It is warm rather than clinical, so flesh painted with it stays alive. The catch is chemical: lead white blackens on contact with sulphur, converting to lead sulphide. In oil this rarely matters, because the oil seals it, but in watercolour, tempera and fresco it does, and there are medieval manuscripts where the white highlights have gone brown-black while everything else survives.
Afterlife
Zinc white arrived in the 1780s and titanium white in 1921, both non-toxic. Zinc is cold and brittle and cracks with age; titanium is enormously opaque and slightly chalky, and it flattens the subtle transitions that lead white made possible. Neither behaves the same under the brush. Lead white was banned for general sale in most countries through the twentieth century — the 1921 White Lead Convention began the process — and is now available only to restorers and professional painters under controls. Conservators still consider it irreplaceable for retouching old paintings, because nothing else ages the same way.
Where it appears
Every era and artist in this atlas whose palette includes this pigment.