Ground Granulated Blast Furnace Slag (GGBS) is a by-product from the blast-furnaces used to make iron. These operate at a temperature of about 1,500°C and are fed with a carefully controlled mixture of iron ore, coke, and limestone. When the iron is extracted, molten slag is left behind. This slag is rapidly quenched in water to form granules, which are then dried and ground into a fine powder to produce GGBS. GGBS is widely used in the construction industry as a supplementary cementitious material (SCM). When mixed with Portland cement, it significantly improves the durability, strength, and sustainability of concrete. Its use helps reduce the carbon footprint of construction projects by replacing a portion of energy-intensive clinker in cement production