Ground granulated blastfurnace slag Wikipedia
Groundgranulated blastfurnace slag (GGBS or GGBFS) is obtained by quenching molten iron slag (a byproduct of iron and steelmaking) from a blast furnace in water or steam, to produce a glassy, granular product that is then dried and ground into a fine blast furnace slag is highly cementitious and high in CSH (calcium silicate hydrates) which is a strength enhancing