Silicon Metal lump was produced in electric heating furnace by quartz and coke. Quartz will be redox and became molten silicon liquid. After cooling, it will be solid as we see. The primal silicon metal lump is very large. Then it will be made into smaller lumps which we call standard size. Silicon Metal Lumps will be 10-100mm. Typical models includes: Silicon Metal 2202; Silicon Metal 3303; Silicon Metal 441; Silicon Metal 553, Silicon Metal Off Grade.