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 cake topper Wedding cake topper A wedding cake topper is a small model that sits on top of a wedding cake, normally a representation of the couple in formal wedding attire. The wedding cake topper was dominant in United States weddings in the 1950s where it represented togetherness. Today, these decorative figurines are often part of the couple's decorative theme or wedding reception style. Traditional wedding cake toppers depict the couple in formal attire and are often the only part of the cake which can be kept over the years, apart from photographs of it. While traditionally the bride and groom were