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
Anniversary Trouble Anniversary Trouble Anniversary Trouble is a 1935 "Our Gang" short comedy film directed by Gus Meins. It was the 134th "Our Gang" short (46th talking episode) that was released. Spanky's appointment as treasurer of the Ancient and Honery Order of Woodchucks occurs on the same day as his parents' wedding anniversary. Spanky's father (Johnny Arthur) puts money in an envelope as an anniversary gift for his wife (Claudia Dell), then absent-mindedly uses the envelope as a bookmark. Spanky's mother sees Spanky hide the gang's club money in a cookie jar and jumps to the conclusion that Spanky stole her gift