Hundred years of the discovery of hafnium

The year 2023 marks hundred years of the discovery of the element hafnium (atomic number 72). Until its discovery, it was believed that the element with atomic number 72 belonged to the group of rare earths. Systematic measurements of the characteristic X-rays emitted by elements when bombarded by cathode rays by Henry Moseley, the evolution of the theory of atomic structure by Niels Bohr and the investigations of George Hevesy along with Dirk Coster, starting with samples of zirconium minerals, led to the discovery of hafnium, and to the clarity regarding the position of element 72 in the periodic table. This note presents a historical perspective of the discovery of hafnium with a brief overview of its separation and applications.