Iron oxide is a chemical compound that is made of oxygen and iron. Iron is a metallic element that is found in approximately 5% of the Earth's crust. When iron oxidizes, or rusts, colors such as yellow, orange, and red are created. A large amount appears on the planet Mars, which is known as the "Red Planet." Mars appears to be red because its crust is composed mostly of this compound. It's commonly known as hematite.
It is thought that deposits of iron oxide were created by the precipitation of iron from sea water during the Proterozoic Eon, some 1.6 billion years ago. These deposits are found in locations around the world, with the greatest concentrations being in the US, India, Australia, China, Brazil, and Russia.
There are three elements that are naturally magnetic: cobalt, nickel, and iron. Among those three, iron is the most magnetic, which is why the oxide form is used extensively in the production of magnets, electronic parts, audio and video cassette tapes, and ATM cards.
In the art world, iron oxide is used to create pigments such as burnt sienna and burnt umber. This method of creating pigments in paint colors has been used since the prehistoric age. The cave paintings at Lascaux are an example of how long this compound has been used in the creation of art.
The cosmetics industry uses the compound to create various pigments in make-up. Because it is non-toxic, water repellent, and does not run or bleed, it is an ideal additive to cosmetics such as mascara, foundation, and eye shadow. There are two different types of compounds used in the cosmetic industry: iron oxide II which has a black pigment, and iron oxide III, which is red.
The different pigments of this compound are used to dye such things as paint, concrete, leather, shoe polish, tiles, and rubber. Brown pigments can range in color from a light brown to a coffee color brown. Red pigmentations range in color from a deep orange to a deep red.
Iron oxide is also added to different nutrients, feeds, and medications. It can be found in certain types of health products, such as talcum powder, facial cream, and body cream. Some sunblock products contain it as well, which helps block UV rays from damaging human skin.