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黄金是人类最早发现和利用的几种金属之一。黄金储备的多少反映了一个国家的贫富。黄金,一个黄而软的金属,比重大(19.3)而硬度很小,但熔点却高达1065℃,故有真金不怕烈火炼的美称。黄金的延展性和可锻性很高,可压成比纸还薄十几倍的金叶,亦可拉成很细的金丝(一克纯金可拉成长达3.5公里的细丝,比蚕丝还细!)。金的导电率仅次于银、铜,为银的74%。 黄金用途很广,素有“百金之王”的美称,主要用作货币和装饰品。如目前,黄金作用为国际贸
Gold is one of the first metals discovered and used by mankind. The amount of gold reserves reflects the wealth of a country. Gold, a yellow and soft metal, a large proportion (19.3) and hardness is small, but the melting point is as high as 1065 ℃, so there is real gold afraid of fierce refining reputation. Gold ductility and malleability is very high, can be pressed into thinner than the paper ten times the gold leaf, can also be drawn into fine gold (one gram of gold can be drawn up to 3.5 km of filaments, than Silk is fine!). The conductivity of gold second only to silver, copper, 74% of silver. Wide use of gold, known as the “King of 100 King” reputation, mainly for currency and decorations. At present, the role of gold for international trade