Not all the content of precious metals in the Earth's crust is little. For example, titanium, zirconium, vanadium content in the Earth's crust than the common non-ferrous metals nickel, copper, cobalt, lead, Tin and zinc. Rare occurrence due to scattered and often associated with other metal, some special physical and chemical properties and often have to take a special production process. As with organic solvent extraction method and the ion exchange method separation extraction lithium, and RB, and cesium, and beryllium, and zirconium, and hafnium, and tantalum, and NB, and tungsten, and MO, and gallium, and indium, and thallium, and germanium, and rhenium and La Department metal, and Actinium Department metal,; with metal hot restore method, and melt salt electrolytic legal take lithium, and beryllium, and titanium, and zirconium, and hafnium, and vanadium, and NB, and tantalum and the re metal,; with chloride metallurgical method extraction separation or restore business take titanium, and zirconium, and hafnium, and tantalum, and NB and re metal,; with iodine of real hot decomposition legal take high pure titanium, and zirconium, and hafnium, and vanadium, and uranium, and thorium,. Vacuum arc melting, electron beam melting, plasma smelting and a series of metallurgical technology has been used to extract rare metals, especially rare and refractory metals. Zone melting technology is the production of high purity rare metals and an effective means of rare and refractory metals.