A study in mauve: unveiling Perkin's dye in historic samples.

The analysis of different historic mauve samples--mauve salts and dyed textiles--was undertaken to establish the exact nature of the iconic dye produced by W. H. Perkin in the nineteenth century. Fourteen samples from important museum collections were analyzed, and it was determined that, in contrast to the general wisdom that mauveine consists of C(26) and C(27) structures, Perkin's mauveine is a complex mixture of at least thirteen methyl derivatives (C(24) to C(28)) with a 7-amino-5-phenyl-3-(phenylamino)phenazin-5-ium core. A fingerprint was established in which mauveines A or B were dominant, and in which mauveines B2 and C(25) were found to be important tracers to probe the original synthesis. Counterion analysis showed that all the mauve salts should be dated after 1862. Perkin's original recipe could be identified in three textile samples, and in these cases, mauveines A and C(25) were found to be the major chromophores. These are now shown to be the samples containing the "original mauve".