dēag

Old English dēag (color, dye, hue) and the related verb dēagian (to dye, to color) have no certain cognates outside English. The word appears in Old English but has no clear Proto-Germanic or PIE ancestor. It may be a very early borrowing from an unknown source, or it may be one of those rare words that originated in Old English itself. The mystery is fitting — the history of dye is the history of secrets, closely guarded recipes, and lost techniques.

Tyrian purple, extracted from the Murex sea snail, was the most expensive dye in the ancient world. Twelve thousand snails produced roughly 1.4 grams of dye. Pliny the Elder wrote that a pound of Tyrian purple cost more than a pound of gold. The dye colored the robes of Roman senators and emperors, and the word 'purple' has meant 'royal' ever since. The color came from a snail. The prestige came from the price.

Indigo, derived from the Indigofera plant, was the world's most important dye for centuries. Indian indigo was traded across the medieval world. European woad (Isatis tinctoria) produced a similar blue but of inferior quality. When synthetic indigo was developed by Adolf von Baeyer in 1880 and commercialized by BASF in 1897, it destroyed India's natural indigo industry almost overnight. The word 'dye' did not change. The economic geography behind it was overturned.

William Henry Perkin, an eighteen-year-old chemistry student in London, accidentally created the first synthetic dye — mauveine — in 1856 while trying to synthesize quinine. The discovery launched the synthetic dye industry, which in turn launched the modern chemical industry. BASF, Bayer, and Hoechst all began as dye companies. The word 'dye' connects a teenage accident to the creation of the world's largest chemical corporations.