Glass defects present inhomogeneities in the matrix of glass. Bubbles, small stones and crystalline inclusions, schlieren and knots depict examples for these inhomogeneities. XRF, XRD, LIBS, REM-EDX and microscopy are used to analyze the nature of solid inclusions.
With knowledge about chemical and crystalline characteristics it is possible to draw conclusions about the glass defects’ cause (f. ex. batch relicts, separations, inclusion of foreign materials, recrystallization and decomposition of fireproof materials). The analysis of bubbles is performed with a mass spectrometer (see also Analysis of bubbles’ content).
(Samples: depending on occurrence)