Determinations Of Ferrous Iron And Total Iron In Glass By A Colorimetric Method - Report Of Icg/Tc2 "Chemical Durability And Analysis"

Technical Committee 2 of the ICG has been requested to establish a reliable method for analysing iron valence states in glass. The optimised procedure is based on cold decomposition of glass sample in an inert gas atmosphere, followed by the spectrophotometric determination of 1, 10-phenanthroline-iron complex after complexing fluoride ions and buffering the solution to a certain pH. 12 laboratories took part in the collaborative investigation in which iron species in glass samples of two different iron contents were determined. The coefficients of variation attained for both ferrous iron and total iron are very good.