Rhenium is the third densest metal after platinum and iridium and has a unique combination of extremely high melting point, high electrical conductivity, and low vapor pressure, making it an ideal material for high-temperature applications. Rhenium is used in superalloys for turbine blades in aircraft engines, heating elements for furnace and thermocouples, catalysts for chemical reactions, and in X-ray tubes for medical and industrial applications. Despite its high cost due to its scarcity, its unique properties make rhenium an indispensable material in various technological fields.