Toilets are made of different materials. The more common toilet bowls and tanks are made from special clay called vitreous china. Vitreous china is a mix of several kinds of clay, called ball clay and china clay, silica, and a fluxing agent. Different types of clay are hardened by first drying in air, then being fired (baked) in a very hot oven called a kiln. Usually a shiny, waterproof coating called a glaze is applied only after a first firing, and the clay is fired a second time. Vitreous china is an exception, in that clay and glaze can be fired together. The whole clay body vitrifies, or turns glassy, so the toilets are actually waterproof and stain proof through its entire thickness.

Some companies manufacture plated metal toilets. You have probably seen them in the airplanes. In the past, toilets were made of different materials like wood, marble, etc. Look at the next web link for interesting information:

toilets

Toilet seats are generally made from one of two materials. Plastic toilet seats are made from a type of thermoplastic called polystyrene. The less expensive and more common type of toilet seat is made from a blend of wood and plastic. The wood is hardwood, usually maple or birch, which has been ground up into the consistency of flour. This wood flour is blended with a powdered plastic resin called melamine. Zinc stearate is a third ingredient in wooden toilet seats. This prevents the wood-resin mix from sticking to the mold in the manufacturing process. The metal tank fixtures are made of stainless steel or copper, and the joints that hold the seat to the bowl are usually a rubber-like plastic.

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