Titanium Dioxide
TiO2 , or titania. is one of the products of the hydrogen reduction of ilmenite. Titanium dioxide occurs naturally in the form of three minerals: anatase, brookite, and rutile.
Titanium dioxide is a transparent, refractory material. Because of its high index of refraction, thin films of titania are sometimes used as an antireflection coating (AR coating) on solar cells.