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 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