Evaluation Of Results From Determination Of B203 In Glass By In-House Methods

The aim of this study is to highlight trouble spots in the methods that are currently used by TC2 members for boron determination in glass. Routine boron determinations in glass are mostly done by volumetric procedures, which are normally considered to be adequate for their purpose. As the volumetric procedure using mannitol is most common among participating laboratories, the findings refer mostly to trouble spots using this technique. Two main sources of systematic errors are highlighted for this technique: quantitative transfer of boron into solution and calibration procedures. Because the errors are small and of the same magnitude but of opposite sign, they tend to cancel each other and make them hard to identify.