Tin pest related problems such as tin whiskers. At 13.2 °C (about 56 °F) and below, pure tin transforms from the silvery, ductile metallic allotrope of β-form "white tin" to the brittle, nonmetallic, α-form "grey tin" with a diamond cubic structure. The transformation is slow to initiate due to a high activation energy but the presence of germanium (or crystal structures of similar form and size) or very low temperatures of roughly −30 °C aids the initiation. There is also a large volume increase of about 27% associated with the phase change to the nonmetallic low temperature allotrope. This frequently makes tin
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