calcarenite
Limestone composed predominantly of cemented sand-size grains of the mineral calcite (more rarely aragonite), usually as fragments of shells or other skeletal structures. Some calcarenites contain oolites (small, spherical grains of calcium carbonate that resemble fish eggs) and may be termed oolitic limestone. Calcareous sandstones, in which the calcium carbonate is present chiefly as bonding material, are not included in this category. (Marble Institute, 2011)