The development of mineralogy, the evolutionary changes in compre hending the mineral substance of the earth are closely associated with the progress of research methods. Over a space of more than two and half centuries, from the goniometry of the mineral crystals to microscopic petrography and optical mineralogy, to crystal structure determinations, electron micros copy and electron diffraction and finally investigations into their electri cal, magnetic and mechanical properties, all this has led to the formation of the existing system of mineralogy, its notions, theories and to a proper...