Tin cry Tin cry A tin cry is the characteristic sound heard when a bar of tin is bent. Variously described as a "screaming" or "crackling" sound, the effect is caused by the crystal twinning in the metal. The sound is not particularly loud, despite terms like "crying" and "screaming". It is very noticeable when a hot-dip tin coated sheet metal is bent at high speed over rollers during processing. The tin cry is often demonstrated as a simple science experiment. The bar of tin will "cry" repeatedly when bent until it breaks. The experiment can then be recycled by melting and
Wedding anniversary for the 50th anniversary, and every fifth anniversary after that. In the United States, a couple can receive a greeting from the President for any wedding anniversary on or after the 50th. Roman Catholics may apply for a Papal blessing through their local diocese for wedding anniversaries of a special nature (25th, 50th, 60th, etc.). The names of some anniversaries provide guidance for appropriate or traditional gifts for the spouses to give each other; if there is a party these can be brought by the guests or influence the theme or decoration. These gifts vary in different countries, but some