Tin per kg over years: In 2006, about half of all tin produced was used in solder. The rest was divided between tin plating, tin chemicals, brass and bronze alloys, and niche uses. Tin has long been used in alloys with lead as solder, in amounts 5 to 70% w/w. Tin with lead forms a eutectic mixture at the weight proportion of 61.9% tin and 38.1% lead (the atomic proportion: 73.9% tin and 26.1% lead), with melting temperature of 183 °C (361.4 °F) . Such solders are primarily used for joining pipes or electric circuits. Since the European Union Waste Electrical
Electrical contacts operation is logically inverted from Form A. An alternate notation for "Form B" is SPST-NC. "Form C" contacts ("change over" or "transfer" contacts) are composed of a normally closed contact pair and a normally open contact pair that are operated by the same device; there is a common electrical connection between a contact of each pair that results in only three connection terminals. These terminals are usually labelled as "normally open", "common", and "normally closed" ("NO-C-NC"). An alternate notation for "Form C" is SPDT. These contacts are quite frequently found in electrical switches and relays as the common contact element