Titanium is extracted mainly from its ore rutile through the chloride process or the Kroll process. In the chloride process, rutile is converted to titanium tetrachloride which is then purified and oxidized back to titanium dioxide. In the Kroll process, titanium tetrachloride is reduced with magnesium to form titanium sponge. Titanium has a silvery metallic color and is strong yet lightweight, making it useful for applications in aircraft, naval ships, implants, and more. It is also consumed to produce titanium dioxide, which has a wide variety of uses.