Melanin ‘dust’ or ‘ghost’?

To definitely verify the dogma of ‘melanin dust’ in the stratum corneum, Tobin et al have now reported a careful review of the literature with a vis-à-vis of the Fontana Masson (FM) and Von Kossa (VK) histochemical methods plus the Warthin-Starry (WS) stain on very thin cryosections of normal human skin and mouse pelage skin epidermis lacking melanocytes. By this approach the authors were able to conclude that: a) WS stain provides a much more sensitive and more specific melanin detection method than the common-place FM stain; and b) that ‘melanin dust’, long purported to be present in the stratum corneum, is most likely an artefact due to non-specific silver deposition in the stratum corneum. The conclusions by Tobin and coworkers raise a number of important issues that are discussed