The GGBFS we supply are according to the standard BS 6699. Ground Granulated Blast furnace Slag (GGBS), A: CaO 34.6% B: SiO2 33.42% C: Al2O3 15.23% D: Fe2O3 15.23% E: MgO 7.21% F: SO3 0.06% G: LOl 0.09% H. Moistre Content 0.1% And we can also supply the GGBS according to your standard.