Crystal structure "white tin" respectively. Two more allotropes, γ and σ, exist at temperatures above 161 °C and pressures above several GPa. White tin is metallic, and is the stable crystalline form at or above room temperature. Below 13.2 °C, tin exists in the gray form, which has a diamond cubic crystal structure, similar to diamond, silicon or germanium. Gray tin has no metallic properties at all, is a dull gray powdery material, and has few uses, other than a few specialized semiconductor applications. Although the α–β transformation temperature of tin is nominally 13.2 °C, impurities (e.g. Al, Zn, etc.) lower the
Wedding cord Wedding cord The traditional wedding cord, also known as the wedding lasso, is a piece of wedding paraphernalia used in some Christian Catholic wedding ceremonies. This is actually a representation of a loop of rosary beads made out of white satin or silk. During the wedding proper, this is traditionally formed into a figure-of-eight shape, and then placed around the neck areas of the bride and the groom after they have made their wedding vows, and are already kneeling on pillows for the pronouncement of a wedding prayer. This cord symbolizes lifetime unity or the everlasting union of the bride