The invention is directed towards a process for complete conversion of multiple industrial wastes to sustainable alternatives and usable products resulting in water in-soluble product alike chemical gypsum useful for cement manufacturing used in construction industry. The inventor has utilized industrial wastes from multiple industries together taking into consideration their chemical and physical properties without using any form of energy. The whole process is carried out at ambient temperature under open sky. In described two exemplary processes, the inventor has disclosed process comprising the steps of mechanically mixing metallurgical inert waste of aged dry Jarofix containing crystallized Gypsum with freshly generated Jarosite or dry / wet Red Mud followed by addition of adequate acidic concentration waste water, calcitic wastes, pozzolanic property enhancers & lime treatment. The multiple wastes mix crystallized chemical gypsum mass on drying is used as a whole without any leftover.