Up to 20% of framework quartz and feldspar grains in wave-reworked sandstones in the Precambrian Bhalukona Formation, central India are replaced by glaucony, which is characterized by high K2O, Al2O3,MgO and low total Fe2O3 content. Textural evidence indicates that incipient glaucony within cleav-ages and fractures of detrital grains evolved to pellets. K2O content of glaucony remains high (av. >8%),despite its low total Fe2O3 content. Glaucony evolved with addition of total Fe2O3 at a constant K2O. During the course of maturation Al2O3was released while total Fe2O3, MgO and SiO2 were added to theglaucony structure. Glaucony originated in a high aK+ and high aSi+ pore water environment by pseu-domorphic replacement of grains. Continental weathering-related supply of Fe, Mg, K and Si facilitatedglaucony formation in shallow marine sediments. The origin, evolution and geochemistry of shallowmarine-originated Precambrian glaucony completely differ from those of their Phanerozoic counterpart.