Glass Clarification With Antimony H Schoenborn

In laboratory tests at a glassworks in Jena, additions of 0.15% Sb2O3 were found to be superior to the equivalent amount of 0.10% Al2O3 insofar as the average blister concentration and the average size of the blisters were concerned. The lower the melting and clarification temperatures, the greater was the effect. In easily melting alkali-rich glasses Sb clarification is also superior to sulfate clarification. A combined clarification of fluorspar and Sb is the most favorable, and quartz meal gives a worse clarification than finely ground sand.