Silicon metal is a gray and shiny semiconductor metal,also known as crystalline silicon or industrial silicon, is mainly used as an additive for non-ferrous alloys which smelted from quartz and coke in an electric furnace.The classification of metallic silicon is usually classified according to the content of iron, aluminum and calcium, silicon metal can be divided into different grades such as 441, 553, 3303, 5502, and Off Grade 97.