An amalgamator is a mechanical apparatus designed to triturate balanced proportions of liquid mercury and metal alloy to produce silver amalgam restorative material. Trituration is the mechanical mixing of mercury and dental alloy resulting in their amalgamation. Amalgam mixers can be used with traditional capsules or premeasured sealed capsules. Traditional capsules are metal or plastic tubes in which dental practitioners can place measured amounts of alloy powder and liquid mercury. Premeasured sealed capsules contain pre-proportioned amounts of metal alloy and mercury that are separated by a non-reactive tin foil to prevent merging during the manufacturing process. Prior to inserting the premeasured capsule in the amalgamator, the tin foil must be punctured by compressing or twisting both parts of the capsule to allow contact between the liquid mercury and metal alloy. Some types of amalgamators can mix a variety of other restorative materials packaged in capsules such as glass ionomer cement.