Rutile (TiO2 and Fe2O3) is a natural source of Titanium with iron impurities and may also contain Silica, Chromium, and Vanadium.  Used to produce ivory to mottled brown colour in oxidation, purples and blues under reduction - especially in combination with a trace of Illmenite. Excellent for modifying other stains or oxides and creating mottled or streaked effects.