Synthetic · Mid-19th century
Low toxicity
Not associated with significant documented toxicity risk in normal use; no restriction on the modern synthetic-dye descendants of this discovery.
Mauveine is not one compound but a family of at least thirteen related molecules sharing a phenazinium core — a positively charged, nitrogen-containing ring system with phenyl and amino groups attached. The main members, mauveines A and B, differ only in how many methyl groups they carry, and absorb around 540–550 nm, taking out green-yellow light and leaving a red-violet. As a cationic (basic) dye it bonds readily to silk and wool proteins.
William Henry Perkin, an eighteen-year-old student in London, was trying to make quinine in 1856 when oxidising impure aniline gave a black residue with a purple extract. Crucially, his aniline contained toluidines, which chemical analysis of museum samples confirms were built into the dye. He patented it, and with his family built a factory near Harrow; the colour became a fashion sensation. Other firms, notably in Germany, produced their own versions with slightly different chemistry.
Mauve was a vivid novelty rather than a durable colour: like other early basic dyes it is regarded as sensitive to light, so an exposed face of a mauve garment may be paler than a protected fold. Studies of related early violets show how far such fading can go — methyl violet in Matisse's cut-outs and a 19th-century silk has faded markedly, and chemical analysis can measure how faded a sample is. For historic dress this means display lighting, not handling, is usually the main risk.
Liquid chromatography with diode-array detection and mass spectrometry separates the individual mauveine molecules; the pattern works as a fingerprint that distinguishes Perkin's product from Caro's German version, and counter-ions in the salts have been used to date samples. SERS can identify it in tiny samples from textiles and paper, and the same chromatography separates mauve from later aniline violets.
Mauveine was superseded within a decade by brighter and cheaper aniline dyes such as fuchsine and methyl violet, and later by acid, azo and reactive dyes that are far faster to light and washing. Modern purples are formulated for fastness rather than discovered by accident. Mauveine survives mainly as a historical and teaching compound — and in its reputation as the start of the synthetic dye industry.
FactStrong evidence
Analysis of fourteen museum samples showed Perkin's mauve is a mixture of at least thirteen methylated phenazinium compounds, not just two, with mauveines A or B dominant.
Source: A study in mauve: unveiling Perkin's dye in historic samples
FactStrong evidence
Perkin's and Caro's mauveine differ chemically in pseudo-mauveine content and in their ratio of C26 to C27 chromophores, which absorb around 540–550 nm.
Source: Reconstructing the historical synthesis of mauveine from Perkin and Caro: procedure and details
FactStrong evidence
Museum samples confirm that Perkin's patented mauveine was made from impure aniline containing o- and p-toluidine.
Source: Chemical archaeology with historical museum samples of mauveine
Colourwise interpretationLimited evidence
Mauve silks are likely to have faded on light-exposed faces, as related early basic violet dyes have been shown to fade markedly in historic silk and paper.
Based on: Measured fading of methyl violet and related early basic violets in a 19th-century silk and Matisse cut-outs; not a measurement of mauveine itself.
Caveat: An inference from chemically related dyes; mauveine's own light-fading has not been quantified here.