Gold bullions are measured in ounce or gram. At present, the most common gold bullions are in 400 ounces (12.5 kg) around the world. Gold bullions are mainly used in international reserves, making of jewelry and decoration, and applications of industries and science and technology. With unique and unrivalled properties, gold is characterized by extremely high corrosion resistance and reliability; good electrical and thermal conductivity; a large effective cross section of nucleus for neutron capture; near 100%reflectivity to infrared rays; various catalytic properties in gold alloys; favorable properties for processing into ultra-thin gold foils, micron-level gold wires and gold powder; easy plating on the surface of other metals, pottery and glass; easy welding and forging under certain pressures; making of superconductors and organic gold. Due to such favorable properties, it is widely used in the most important modern high-tech industries, such as electronics, telecommunications, aerospace, chemical, medical and so on.