Iron can be found in the Earth's core, in the Earth's crust, in hemoglobin, in steel and in magnets. It is rare to find iron in its elemental form on Earth, but it has been found in igneous rocks in Russia.
Iron is a shiny gray metal. When it oxidizes, the resulting compound is known as iron oxide or rust. Iron rusts in damp air but not in dry air. Iron is the fourth most abundant element on Earth and the tenth most abundant element in the universe. It is ductile and malleable and is the most used of all the metals. Two useful forms of iron are wrought iron and steel. Wrought iron is strong and can be welded and forged. Steel is used for surgical instruments, drills and other tools.
Iron is found in hemoglobin. Hemoglobin is a component of red blood cells that transports oxygen from the lungs to body tissue. Iron can also be found in myoglobin which takes oxygen from hemoglobin and holds it in the muscles until it is needed. Iron is present in meat and vegetables, but the human body absorbs iron faster from animal products than plants. Not having enough iron in the body can cause iron deficiency which can lead to anemia.