Assay measurements of oxide materials by thermogravimetry and ICP-OES

Purity data for inorganic chemicals are usually on metals basis. A high nominal purity does not guarantee that the material has the theoretical assay value. Deviations range from some tenth % (CaCO3) up to ≈10% (La2O3) for commercial chemicals with nominal 99.999% purity. In critical cases, ICP-OES and/or TG measurements provide good ways to obtain quantitative assay data and to define conditions that lead to the desired results of synthesis processes as crystal growth.