Alizarin crimson

Origin

Alizarin is the principal colouring compound in madder root. In 1868 Carl Graebe and Carl Liebermann, working at the Berlin firm that would become BASF, determined its structure and synthesised it from anthracene, a coal-tar derivative; William Perkin arrived at a commercially viable route almost simultaneously in England, filing a patent one day after the German team. The consequence was immediate and brutal: madder was grown on tens of thousands of hectares in France, the Netherlands and the Levant, and within a decade that industry was gone. The synthetic product was cheaper, stronger, more consistent and free of the purpurin that made natural madder shift hue.^{[1, 2]}

In art history

It appears in eight eras of this atlas, all of them after 1870, and it became the standard transparent red of modern painting — the crimson on virtually every twentieth-century palette, and the colour painters reach for to darken a red without dulling it or to glaze a shadow. It is also, historically, the first proof that a natural product could be manufactured more cheaply than it could be grown, a demonstration that reorganised the chemical industry and set the pattern for synthetic indigo, synthetic vanilla and everything after.

In the studio

It is intensely transparent and very strong, so it glazes beautifully and stains anything it touches. Mixed with white it gives clean cool pinks; mixed with ultramarine it gives the violets that were difficult before. It dries slowly in oil and forms a somewhat weak film, so it is best kept to upper layers and glazes. The serious issue is lightfastness. Alizarin was long sold and taught as permanent, and it is not: in thin applications and in tints it fades measurably, and testing since the mid-twentieth century has consistently rated it poor. A great many twentieth-century paintings have crimsons that are weaker than they were.^{[3, 4]}

Afterlife

Most manufacturers now offer alizarin crimson hue, built from quinacridone, which is visually very close and genuinely lightfast, and some have discontinued the original entirely. The traditional pigment is still sold, largely because painters know the name and the handling, and it remains one of the clearest cases in the field of reputation outliving performance.

In different media

Oil

Transparent, and weakest exactly where it is most used: thin glazes and pale tints fade far faster than the full-strength colour.^{[3, 4]}

Replacing alizarin crimson