Tin be toxic. Tin in combination with other elements forms a wide variety of useful alloys. Tin is most commonly alloyed with copper. Pewter is 85–99% tin; bearing metal has a high percentage of tin as well. Bronze is mostly copper (12% tin), while addition of phosphorus gives phosphor bronze. Bell metal is also a copper–tin alloy, containing 22% tin. Tin has sometimes been used in coinage; for example, it once formed a single-digit percentage (usually five percent or less) of American and Canadian pennies. Because copper is often the major metal in such coins, sometimes including zinc, these could be
Antimicrobial copper-alloy touch surfaces antimicrobial efficiency tests include: The registrations are based on studies supervised by EPA which found that copper alloys kill more than 99.9% of disease-causing bacteria within just two hours when cleaned regularly (i.e., the metals are free of dirt or grime that may impede the bacteria's contact with the copper surface). To attain the EPA registrations, the copper alloy groups had to demonstrate strong antimicrobial efficacies according to all of the following rigorous tests: The alloy groups tested and approved were C11000, C51000, C70600, C26000, C75200, and C28000. The EPA registration numbers for the six groups of alloys are as