Limburg chalk
Chalk is a soft, white, porous form of limestone composed of the mineral calcite (CaCO3). It is also a sedimentary rock. It is relatively resistant to erosion.
en-US/ˈlɪmbɚɡ ˈt͡ʃɔk/
Chalk is a soft, white, porous form of limestone composed of the mineral calcite (CaCO3). It is also a sedimentary rock. It is relatively resistant to erosion.