Tin bent, a crackling sound known as the "tin cry" can be heard from the twinning of the crystals. Tin melts at low temperatures of about , the lowest in group 14. The melting point is further lowered to for 11 nm particles. β-tin (the metallic form, or white tin, BCT structure), which is stable at and above room temperature, is malleable. In contrast, α-tin (nonmetallic form, or gray tin), which is stable below , is brittle. α-tin has a diamond cubic crystal structure, similar to diamond, silicon or germanium. α-tin has no metallic properties at all because its atoms form
Diplomatic gift A 2012 gift of a "British" table tennis table to President Obama seemed ideal until it was revealed that it was designed in Britain but made in China, evoking worries about the decline of British manufacturing industry. Diplomatic gifts take diverse forms: Diplomatic gift A diplomatic gift is a gift given by a diplomat, politician or leader when visiting a foreign country. Usually the gift is reciprocated by the host. The use of diplomatic gifts dates back to the ancient world and givers have competed to outdo each other in the lavishness of their gifts. Examples include silks given to