“…The particles of the metal itself may contribute to the colour of skin and can often be demonstrated directly in sections (Burge & Winkelmann, 1970). However, in the absence of a proper history of intake, the identification of the metal may present difficulties and it may be necessary to employ ultrasensitive techniques like neutron activation analysis (Schropl, Oehlschlaegel & Drabner, 1968).…”