a mixture of dry ingredients capable of forming a crosslinked polymer upon hydration for use as a fracturing fluid in processes for recovering minerals from subterranean formations . the dry mix comprises a polysaccharide , a crosslinking agent selected to become active after the polysaccharide has been substantially hydrated , and a ph - adjusting agent to facilitate the crosslinking reaction . the mix is hydrated while being pumped and reaches maximum viscosity in the subterranean formation .