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 noticed by the referee. Records indicated that there were two preliminary matches on the September 24th show, but records of neither the participants nor the actual results of these matches have been confirmed. The third match of the night featured Rito Romero wrestling against Black Shadow, but no record of who won is found. Likewise the results of the fourth match between Gory Guerrero and Bobby Bonales are also undocumented. In the main event NWA World Middleweight Champion Tarzán López successfully defended the championship against the challenger Harry Fields in a Best two-out-of three falls match. EMLL 15th Anniversary Show