repeated except that instead of the co ai o colouring body a yellow colouring body of the system zr si pr o commercially available product no fz 347 from bayer ag leverkusen is employed after incorporating 5 wt of the colour granulate in a transparent enamel see example 1 a yellow enamel coating is obtained which exhibits high gloss hiding power and colour intensity the same procedures of example 1 are repeated except that a red colouring body of the system zr si fe o commercially available product no fz 805 from bayer ag leverkusen is employed after incorporating 5 wt of the colour granulate in a transparent enamel see example 1 a red enamel coating is obtained which exhibits high gloss 3 8 wt of the yellow colour granulate of example 1 are incorporated together with 1 2 wt of the blue coloured granulate of example 1 in the transparent enamel frit see example 1 there is obtained a dark green enamel with high gloss and hiding power 3 8 wt of the yellow colouring body of example 1 are incorporated together with 1 2 wt of the blue colouring body of example 1 in the transparent enamel frit see example 1 there is obtained a weak dirty.