The present disclosure provides a ready-to-use seed composition water, a source of silica, a source of alumina, and Na20, wherein the molar ratio of H20:Na20 ranges from 5 to 20, Na20:SiO2 ranges from 0.4 to 5 and SiO2:Al203 ranges from 1.3 to 5 used in the preparation of a synthetic faujasite zeolite which has high thermal stability and higher crystallite size. It further provides a process for preparing the ready-to-use seed composition for preparation of synthetic faujasite zeolite that requires lower crystallization time. The present disclosure provides a seed composition that does not require maturing time and a reaction gel composition that has low water and soda content. The present disclosure further provides a process for the preparation of synthetic faujasite zeolite by blending seed and reaction gel reaction composition to form a seed gel composition and subjecting it to crystallization.