Limestone is a soft and porous stone, which means that its surface can be easily scratched. Since it too is primarily made from calcite, it is at a 3 on the Mohs scale of hardness. Again, this creates problems in the kitchen, since cutting utensils are rated quite higher and a single slip of the knife can lead to scratches. Like both marble and travertine, limestone is weak against acidic liquids. Any spills left on its surface that contain slight amounts of acid, like fruit juice, can quickly eat into the stone, creating additional scratching. Therefore, this stone is not recommended for kitchen countertops, though it can be used for kitchen floors.