Carbon Dioxide (CO2) is a byproduct of cement manufacturing process. It is produced in huge quantities while manufacturing Ordinary Portland Cement (OPC). Production of Ordinary Portland Cement Concrete (OPCC) utilizes large quantities of energy and natural resources. Geopolymer Concrete (GPC) came as an alternative to Ordinary Portland Cement Concrete (OPCC). In the present work, silica fume has been used as a replacement to Ground Granulated Blast Furnace Slag (GGBS). This study mainly presents the mix design steps and the mechanical properties of the GPC. The mix design proportions for the GPC were based on trial and error. GGBS from the mix proportions was replaced with Silica Fume in the percentages of 20%, 40%, 50%, 60%, 80%, and 100%. The mechanical properties like compressive strength, split tensile strength, flexural rigidity, and modulus of elasticity were studied for all the replacements. It was shown that the specimens with only GGBS as source material are high in strength. It was observed that the properties like compressive strength, split tensile strength, flexural strength showed a significant reduction with the increase in silica fume quantity. A delay in the setting time of GPC was observed with the increase in Silica Fume content.