Gold 101

Gold , symbol Au (from Latin aurum,"gold"), soft, dense, bright yellow metallic element. Gold is one of the transition elements of the periodic table (see Periodic Law); its atomic number is 79.

Pure gold is the most malleable and ductile of all the metals. It can easily be beaten or hammered to a thiczkness of 0.000013 cm (0.000005 in), and 29 g (1.02 oz) could be drawn into a wire 100 km (62 mi) long. It is one of the softest metals (hardness, 2.5 to 3) and is a good conductor of heat and electricity. Gold is bright yellow and has a high luster. Finely divided gold, like other metallic powders, is black; colloidally suspended gold ranges in color from ruby red to purple (see Colloid). Read more »