pb3o4

massicot \mas"si*cot\, n. [F. massicot; E. masticot is a
   corruption.] (Chem.)
   Lead monoxide (also called {Lead protoxide}), {PbO}, obtained
   as a yellow amorphous powder, the fused and crystalline form
   of which is called {litharge}; lead ocher. It is used as a
   pigment. It is also called {lead oxide yellow}, as opposed to
   {red lead}, which is lead tetroxide {Pb3O4}.
   [1913 Webster +PJC]

   Note: Massicot is sometimes used by painters, and also as a
         drier in the composition of ointments and plasters.
         [1913 Webster]
    

minium \min"i*um\ (?; 277), n. [L. minium, an Iberian word, the
   Romans getting all their cinnabar from Spain; cf. Basque
   armine['a].] (Chem.)
   A heavy, brilliant red pigment, consisting of an oxide of
   lead, {Pb3O4}, obtained by exposing lead or massicot to a
   gentle and continued heat in the air. It is used as a cement,
   as a paint, and in the manufacture of flint glass. Called
   also {red lead}, {lead tetroxide}, {lead orthoplumbate},
   {mineral orange}, {mineral red}, {Paris red}, {Saturn red},
   and less definitively, {lead oxide}.
   [1913 Webster]