Microwave digestion is a well-established preparation technique for converting solid samples into solutions suitable for analysis by ICP-AES, ICP-MS, atomic absorption spectrophotometry or polarography. The solid sample is chemically digested using a liquid reagent (usually a mineral acid) by microwave heating in a closed container. By heating in a closed container, temperatures in the range of 200-260 °C (far in excess of the boiling points of the acids) can be generated, which accelerates the digestion process. A typical microwave digestion takes just 20-40 minutes making it a powerful preparation tool for the analysis