Molybdenum is mainly used in the steel industry. It always appears in the form of various oxides in minerals. In the form of a single element, molybdenum is a gray metal with a gray cast iron color. It is easier to form hard, stable carbides in the alloy, so most of the world's molybdenum products (about 80%) are used as some kind of iron alloy, including high-strength alloys and high-temperature alloys.