Embodiments herein provide a method of preparing Silicon (Si) from sand (SiO2).The method includes preparing sand particles with a size less than 50 microns. Further, the method includes obtaining Magnesium (Mg) particles with a size in range of 105-150 microns. Further, the method includes mixing sand and Mg particles in a predefined ratio to obtain a Sand-Magnesium (SM) mixture. Further, the method includes subjecting the SM mixture to heating at a temperature for a predefined time to obtain Si sample. Further, the method includes identifying un-reacted portion of Mg and sand particles. Furthermore, the method includes purifying byproducts of magnesium as well as un-reacted-magnesium and silica to obtain pure Si.