Iridium is a silvery-white, hard and brittle precious metal that belongs to the platinum group of metals. It was first discovered by Smithson Tennant in 1803 and is named after the Greek word “iris”, which means rainbow. Here is how it is characterized by the essential properties of precious metals:
- Rarity: Iridium is one of the rarest elements on Earth, with an average concentration in the Earth’s crust of just 0.001 parts per million. It occurs only in trace amounts in the Earth’s crust and is mainly found in asteroids.
- Durability: Iridium is extremely durable and resistant to corrosion and oxidation. It is also very hard, making it useful for industrial applications that require strong materials.
- Malleability: Iridium is very difficult to shape and form due to its high melting point and hardness. However, it can be alloyed with other metals, such as platinum, to make it more malleable. Iridium is very corrosion resistant, and can withstand high temperature and pressure. It is therefore widely used in the aviation industry and for the production of rocket engines, as well as laboratory equipment.
- Conductivity: Iridium is an excellent conductor of electricity and is commonly used in spark plugs and other electrical components due to its corrosion-resistance and high-temperature resistance.
- Beauty: Iridium is a silvery-white metal with a high luster, making it a popular choice for jewelry and other decorative items.
- Absorbing Hydrogen: Iridium has a remarkable ability to absorb hydrogen gas. This makes it an important material for the production of co-catalysts in fuel cells.
- Organo-iridium: Iridium is also used in medicine, especially in the treatment of cancer. A promising approach is to transport organo-iridium complexes into cancer cells and then activate them from the outside by laser irradiation.
Iridium is primarily used in the production of catalysts for the chemical and petroleum industries. It is also used in spark plugs, electrical contacts, and other electrical components due to its high conductivity. In addition, iridium is used in jewelry and other decorative objects.
Iridium is primarily found in South Africa, Russia, and Canada. South Africa is the largest producer of iridium, followed by Russia.
The price of iridium has fluctuated over the years, with its highest price in recent years being around $4,000 per ounce in 2008 during the global financial crisis. In 2021, the price of iridium was around $6,000 per ounce, driven by increased demand for use in fuel cell technology.