BCS Ferro-Silicon is a 75% concentration of FeSi used to improve the machinability of Cast Irons.
Only a small quantity of 75% Ferro-Silicon additive is needed. Commercial foundries use about 7 to 14 lbs per ton. You will need to experiment a bit to determine the amount that works best for your melt size. BCS Ferrosilicon is supplied in a 3/8in x 12 mesh particle size. The chemical analysis is 75.22% Si, 0.96% Al, 0.75% Ca.Quart Can contains about 3 Lbs