Silicone is derived from silicon, a semi-metallic or metal-like element that, in nature, combines with oxygen to form silicon dioxide, or silica. Beach sand, crystals, and quartz are silica, which is the most common substance on earth. Heating silica with carbon at a high temperature can produce silicon. Further processing can convert the silicon into a long chemical chain, or polymer, called silicone - which can be a liquid, a gel, or a rubbery substance. Various silicones are used in lubricants and oils, as well as in silicone rubber. Silicone can be found in many common household items, such as polishes, suntan and hand lotion, antiperspirants, soaps, processed foods, waterproof coatings, and chewing gum.