Determination of Several Valences of Iron, Arsenic and Antimony, and Selenium in Glass

Methods for the analysis of silicate glasses are described for ferrous iron, for tri- and pentavalent arsenic and antimony when present together, and for selenium as Se^2-, Se°, Se⁴⁺, and Se⁶⁺. Analytical results are presented for FeO in the range 0 to 0.25%; for total As and Sb as tri-oxide, 0.1 to 1.25%; and for total Se, 0.05 to 0.25%. Apparatus for the determination of FeO is described, and a comparison is made of analytical data for FeO versus light transmittance at 1000 and at 1050 mμ for the same glass.