The role of mineralogy in materials science

After summarizing increasing involvement of mineralogy into the inorganic material technology during the last 50 years, the author mentioned the environmental mineralogy and nanomaterials technology as the most promising fields where mineralogy can now play important roles. As for the X-ray crystallography, in which the author has been engaged for long, it is important to transmit knowhow in structure analyses to the following generation. X-ray determination of electron-density distribution is expected to contribute development of new functional materials with the strongly correlated electronic states, i.e. functional materials for spin and/or orbital electrons.