Metallic silicon, also known as crystalline silicon or industrial silicon, is mainly used as an additive for non-ferrous alloys. Metallic silicon is a trade name that appeared in the mid-1960s. Its emergence is related to the rise of semiconductor industry. The international common practice is to divide commercial silicon into metal silicon and semiconductor silicon. Metallic silicon is a product made of quartz and coke by smelting in an electric furnace. The content of silicon element, the main component, is about 98% (99.99% of silicon is also contained in metallic silicon), and the rest impurities are iron, aluminum, calcium, etc. Semiconductor silicon is high-purity metal silicon used to make semiconductor devices. It is sold in the form of polycrystalline and single crystal. The former is cheap, while the latter is expensive. It is divided into various specifications due to its different uses. According to statistics, in 1985, the world consumed about 500000 tons of metallic silicon, of which metallic silicon for aluminum alloys accounted for about 60%, less than 30% for silicone, about 3% for semiconductors, and the rest for steel smelting and precision ceramics.