Explanatory notes
… Zinc dust Dust obtained by condensation of zinc vapour, consisting of spherical particles which are finer … coke in closed retorts. The temperature is sufficient to vaporise the zinc which distils over into condensers where … may be used directly for galvanising, or may be refined by various methods. Some impure metal is also deposited …Legal note
… Zinc dust Dust obtained by condensation of zinc vapour, consisting of spherical particles which are finer …