Iridium is a chemical element represented by the symbol "Ir" and the atomic number 77. It belongs to the platinum group of metals and is a hard, dense, and lustrous transition metal. The name "iridium" originates from the Greek word "iris," meaning rainbow, due to the various colors observed in the salts of this element.
In nature, iridium is typically found in conjunction with other platinum group metals. It is a rare element, making up only parts per billion of the Earth's crust. The most notable source of iridium is meteorites, where it is found in higher concentrations.
Iridium possesses remarkable physical and chemical properties, such as exceptional resistance to corrosion and heat. It is highly dense and has one of the highest melting points among the naturally occurring elements. Due to its resistance to corrosion, it finds application in various industries, including scientific instruments, electrical contacts, and as a coating for rocket engine nozzles.
Moreover, iridium has unique optical properties, especially in its metallic state. Thin films of iridium can behave as selective light absorbers or reflectors, making them valuable in optoelectronic and optical devices. In addition to its industrial applications, iridium is also used in jewelry due to its exceptional resistance to tarnish.
Overall, iridium is an uncommon and valuable chemical element possessing distinctive physical and chemical properties, prominently utilized in different industries for its resistance to corrosion, heat, and optical capabilities.
