Tribasic lead silicate, 3PbO · SiO2, is a reddish yellow powder, sparingly soluble in water. Its composition by weight is 92% PbO and 8% SiO2. Tribasic lead silicate is available as granular, <1.68 mm (10 mesh), and ground, 99% through 44 μm (325 mesh). It is used primarily by glass and frit manufacturers and has the lowest viscosity of the three commercial lead silicates. Commercial lead silicates are generally prepared by melting lead monoxide and silica in the desired ratio.
