Gravimetric analysis is a quantitative method based on the determination of the mass of an analyte using an analytical balance, which is an instrument of high accuracy and precision. The essence of classic analysis is that the compound or element, which is contained in a solution, is translated into a sparingly soluble precipitate through the process of precipitation, which is further separated from the solution by using filtration. The separated precipitate is then washed, dried or annealed and its mass is measured. The mass of the analyte is calculated from the mass of the obtained precipitate. Thermogravimetric analysis is a method of thermal analysis in which the amount and rate of change of sample mass as function of temperature or time in a controlled atmosphere is continuously measured. Measurement data in thermogravimetric analysis are represented by curves called thermograms, and the shape of a curve depends on the conditions of the experiment itself. Electrogravimetry is a method of electrolytic extraction of pure metal at a cathode and two methods of electrogravimetric determination are commonly used: with constant current and with the constant potential of a working electrode.