The Technical Committee on Properties of glass Forming Melts of the ICG carried out a round robin test on measuring the liquidus temperature of three different industrially produced soda-lime-silica float glass samples. Experimental results from six laboratories have been compared and the experimentally derived data on liquidus temperatures and the primary crystals found have been interpreted with the aid of thermodynamic modeling results. The liquidus temperatures of the given typical float glass compositions were measured by some laboratories to be around 970 deg C and by some other labs to be around 1010 deg C. The deviation can be explained by kinetic limitations of formation of primary crystals during slow cooling of a silicate melt for some experimental procedures.
