This is made based on:
mineral content is the types of minerals contained in this stone.texture of rock, the size and shape of mineral hablur-hablur in batustruktur rock, the mineral crystal arrangement in stone.process formation

Removable rocks that we can find on the banks of the river.
The rocks in general are usually divided according to the process that formed them, and are thus divided into three large aggregates:
rocks of sediments of metamorphic sediments.
Frozen rocks are rocks formed from the liquid mammary, sedimentary rocks formed from sediment deposits and pressures of certain materials, and metamorphic rocks through one of the two former ways which are then changed by temperature and pressure. In cases where organic matter leaves its mark on rocks, these results are identified as fossils.