Ferrosilicon
The silica source for producing ferrosilicon is usually quartzites of lump size 20 to 80 mm, subjected to prewashing, crushing, and grading if needed. Quartzites suitable for smelting of ferrosilicon must contain not less than 97% SiO 2 and not more than 1.5% Al 2 O 3. The carbon reductant is usually nut-coke of 5 to 20 mm in size, but as