Crystal bar process
（重定向自Iodide process）
The crystal bar process (also known as iodide process or the van Arkel–de Boer process) was developed by Anton Eduard van Arkel and Jan Hendrik de Boer in 1925. This process was the first industrial process for the commercial production of pure ductile metallic zirconium. It is used in the production of small quantities of ultra-pure titanium and zirconium. It primarily involves the formation of the metal iodides and their subsequent decomposition to yield pure metal. This process was superseded commercially by the Kroll process.