Limestone vs Sandstone

Our match-up in this comparison article features two materials with one-word names; both of which end with a syllable composed of the word "stone". Yet, the first syllable highlights the difference between these materials. In this article that matches limestone vs sandstone we are going to peer into the properties of these two natural stone surfaces and see just how they compare. Along the way we will briefly mention some of the characteristics that make these materials the choice of builders, designers, and architects.

Characteristics of Limestone

The first material in our comparison that we are going to peruse is limestone. It is a natural stone that has a large amount of calcium carbonate in it. Thus, it is one of several natural stone materials that are classified as calcareous.

A Soft Spot for Limestone

The fact that limestone is made up of a large amount of calcium carbonate means that it is a relatively soft material as far as natural stone goes. The softer the material, the easier it is to scratch. However, soft stone is also easier to cut and to shape than harder materials are.

Poring Over Limestone's Properties'

Another trait that we want to look at briefly is limestone's porosity. All natural stone has a degree of porosity, and limestone is no different. But like other materials, natural limestone varies in porosity from one slab to the next. It is a characteristic that is found in virtually all natural stone slabs. One slab simply might be more porous than the next. This is true though of any natural stone; not just limestone.

An Historical Material

Natural limestone is a unique material in another way. This stone often forms at the bottom of ocean floors, and because of this it ends up having fossils in it. This characteristic of limestone not only contributes to the intrigue, but also means that it brings with it an historical record, as it were.

The properties of limestone we have discussed all contribute to its identity as one of several natural stone materials used for hard surfaces. Often times it is found underfoot in pool surrounds or in other high moisture areas. In these cases, the porosity we mentioned above makes the surfaces less slippery since they absorb the moisture. So that is a brief overview of limestone. But what do we note about sandstone? Let's get into that now.

Sandstone's Properties

In contrast with the first material we looked at, our second is not calcareous like the other. Rather, it is what is known in the stone industry as a siliceous stone. Like other natural stone materials, the make up of sandstone affects its properties. So let's peruse the traits of natural sandstone and see what makes it, its own unique kind of stone.

Siliceous stone is rock that is made up of silica. This mineral is harder than the calcium carbonate in limestone. As a result, sandstone is hard and scratch resistant. The hardness of stone materials is measured using a test known as a scratch test. In this test, tools are used to attempt scratching the stone. Various tools are used to narrow down the hardness of the stone. A stone's hardness is rated by a number ranging from 1 to 10. The limestone we talked about earlier lives in the range of 3 to 4 on the hardness scale. Yet, sandstone resides at around 6. Sandstone's hard nature means it must be fabricated using tools designed for hard stone. Often times professionals will use granite or quartz blades to cut sandstone slabs because these blades are rated for hard materials like sandstone.

Sandstone is Not a Pore Sport

When it comes to porosity, sandstone is much like limestone in the sense that it too varies in porosity from one stone to the next. One thing though that is perhaps very different is the fact that sandstone's range may be wider. In other words, the porosity of sandstone probably varies to a greater degree that limestone. Why do we say that? Well, sandstone is a sedimentary rock that gets transformed into yet another type of rock by metamorphosis. That resulting rock is called quartzite and it is very dense and has very low porosity. Depending on how far along in the metamorphic process a sandstone slab is, it can have high porosity or low porosity. It's counterpart, limestone, is also a sedimentary rock and it too goes through a metamorphic process that transforms it into a totally different stone. Namely, marble. Yet, difference in porosity between marble and limestone is not as wide as that between sandstone and quartzite.

Teeming With Texture

Just as the previous natural stone we discussed is alive with historical information, sandstone is chock full of texture. After all, it is made up of sand particles that have been bound together with some form of cement. The colors of sandstone range anywhere from white to the rich red colors like those seen in the Southwest United States.

As we have seen in this article discussing the traits of these two materials; limestone vs sandstone, each of these materials brings a unique set of characteristics to the proverbial party. However, they also share some common properties that go with the territory of natural stone. Knowing how the hardness, porosity, and texture play a role in how you fabricate the material is key.