Antimony Oxide - Sb2O3

Antimony oxide is used as an opacifier in low fire glazes and porcelain enamel (mainly leadless but it has been replaced to an extent by titania). Antimony is easily reducible; thus an oxidizing agent like potassium nitrate may be required to prevent it from going into solution and losing its opacifying power and affecting color.-It is not useful in glazes over cone 1 due to volatilization.-Antimony can be used as a yellow body stain in combination with rutile or titanium.-Antimony will bleach the surface of low fire red-burning clay to a buff color to produce variegated coloration.-The glass industry uses antimony as a decolorizing and fining agent to clarify glasses and as a stabilizing agent in the production of emerald green glass.-Antimony has a low thermal expansion and reduces crazing.