Iridium is a corrosion-resistant metal that is often used in industrial and engineering applications. It is a transition metal that is part of the platinum group of elements, and is one of the densest elements known to man. Iridium is highly resistant to corrosion, making it an ideal choice for use in environments where other metals may be prone to corrosion. It is also very strong and has a high melting point, making it suitable for use in high-temperature applications.