Choosing natural stone for your construction work can be a tricky task. Of course everyone knows that natural stone has a bespoke and elegant appearance, and you can no doubt tell the difference between groups such as granite and slate versus sandstone and limestone. But picking out the distinctions for building work beyond that can be more difficult, but no less an important familiarisation to make before committing to your stonework project. Sandstone and limestone are both popular materials stone masonry, however they have very distinct qualities that make their uses entirely different in construction.
Unique Formation & Composition
Before you can understand the qualities of sandstone and limestone, it’s important to get your head around the formation process for each. Both are sedimentary rocks, but they have unique ways of being created. Limestone is formed gradually on the bed of oceans and lakes, from living organisms such as molluscs and corals that come together over thousands of years to form rocks. As such, they are often high in calcium carbonate. Sandstone, on the other hand, has almost the opposite formation process. Sandstone is created as other rocks break down over time, for instance by weathering and erosion, to form sand-like minerals that gradually form a new type of natural stone – sandstone.
Qualities & Uses
Because limestone has been created from fine matter crystallising over a long period of time, it is denser and appears to be more of a solid matter than sandstone. This also makes it less porous than the latter, meaning that it is less likely to be subject to the effects of frost and thawing, or staining from pollution. Having said this, as a calcareous rock limestone can be eroded by acid. Rainwater often contains traces of acidity, meaning that over time limestone can be seen to erode despite being less porous. Sandstone, on the other hand, is not as soft as limestone, and is much more durable against the elements due to its hardness and strength as a building material.
Because of these above qualities, limestone is more commonly used to make other building materials such as concrete. Although you will see it used all over the country in dry stone walls, sandstone is much more preferable for paving, walls, and structures, as it is relatively easy to shape and is renowned for its durability. As such, it’s clear to see that although many people group these two sedimentary rocks in the same pod, they are indeed very different types of natural stone that lend themselves to different uses.
Natural stone can vary greatly between each type of stone, and although a professional stonemason will advise you on the best type to use before you commit to any building project, it can be helpful to understand the differences between certain stones yourself. Sandstone and limestone are both essential to modern construction in their own ways, and an understanding of their differences allows you to make informed choices on your next stonework project.