There are many minerals needed by animals, one of them is calcium that prospers their growth, development and production. Calcium is a main source of formation in the bone and teeth in the animals. Calcium carbonate (ground limestone) is a cost-effective source for animals. Elemental calcium in feed grade limestone is as high as 40%. Our company offered free grade limestone in both, powder and granules forms. Offered as a pure calcium carbonate, its physical characteristics include â¥ 90% whiteness, â¤ 0.2% moisture, and â¥ 85% dry brightness. The chemical components that combine to make limestone are CaCO3, Ca, MgO, Fe2O3, Al2O3 and SiO2. PP bags are used for packaging limestone granules and powder.