Tin cry recrystallizing the metal. The low melting point of tin (only 232 °C, or about 500 K) makes re-casting easy. Tin anneals at reasonably-low temperature as well, normalizing tin's microstructure of crystallites/grains. Although the cry is most typical of tin, a similar effect occurs in other metals, such as niobium, indium, zinc, cadmium, gallium, and mercury. 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
Wedding anniversary at the Chicago Public Library. Wedding anniversary A wedding anniversary is the anniversary of the date a wedding took place. Traditional names exist for some of them: for instance, fifty years of marriage is called a "golden wedding anniversary" or simply a "golden anniversary" or "golden wedding". The historic origins of wedding anniversaries date back to the Holy Roman Empire, when husbands crowned their wives with a silver wreath on their twenty-fifth anniversary, and a gold wreath on the fiftieth. Later, principally in the twentieth century, commercialism led to the addition of more anniversaries being represented by a named gift.