Which is it: Marble or limestone?
Marble and limestone are like two peas in a pod – if one of those peas was exposed to extremely high pressure and temperatures and subsequently became a much denser version of the other pea.
In other words, they're similar but different enough for it be an issue. Where this can become a dilemma is when you need a specific product for sealing one of them, but can't for the life of you tell the difference.
For example, say you have stone tiles around a salt water swimming pool. If it were milestone, you would do particularly well to seal the tile up with DRY-TREAT 40SK™. But how can you be sure it's not marble? And how can you have the peace of mind to know your stone has the premium protection?
Here are a few of the ways to tell these two stones apart.
The presence of fossils
Limestone is a sedimentary rock, and is formed from the compression and solidification of sand, mud and shells. In a way, limestone is like one great big museum in a stone.
As such, it has a different appearance and texture to marble. While the limestone used for your tiling is no doubt polished and smoothed out, if you take a magnifying glass or microscope, you should be able to see bits of fossilized shell.
In the same vein …
By contrast, marble is well-known for its distinctive vein patterns, formed from the presence of many different minerals and grains in its surface. If your tile is displaying this well-known characteristic, there's a good chance you're looking at marble.
Are you getting the tint yet?
There are certain colour characteristics to each stone. Limestone tends to come in a limited amount of colours: tan, gray or buff, according to the Marble Institute of America. By contrast, marble can come in just about any color of the rainbow – even a dark, multi-colored iteration known as 'Ebony Gold', which is red, gray, green and brown all at once.
Armed with this knowledge, you can know whether it's limestone or marble protection you're fixing to undertake.