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
EMLL 15th Anniversary Show EMLL 15th Anniversary Show Mexican professional wrestling promotion Empresa Mexicana de Lucha Libre (EMLL) commemorated their 15th anniversary with two "'EMLL 15th Anniversary Shows". The first Anniversary show was held on September 22, 1948 in Arena Coliseo in Mexico City, Mexico, EMLL's main venue. The second event took place two days later on September 24, 1948 in Arena Modelo. The events commemorated the 15th anniversary of EMLL, which would later become the oldest professional wrestling promotion in the world. The Anniversary show is EMLL's biggest show of the year, their Super Bowl event. The first anniversary show featured the EMLL