Does oxidation impact the finish of stone tiles?

The right finish can prevent oxidation and yellowing.

Oxidation creates unsightly yellow staining that nobody wants on their natural stone. Understanding the characteristics and properties of the stone you're working with means you can take the necessary steps to prevent oxidation from the beginning. The most important thing is to stop moisture from getting into the stone, and to stop outside dirt from contaminating it. To do this, you'll need to pick the right sealer and understand how to maintain your natural stone.

What is oxidation in natural stone tiles?

Your stone tiles may start to look yellow or, in more serious cases, brown.

Because natural stones are just that – natural – and form over millions of years in different areas of the world, they are exposed to a range of elements and minerals, including iron. Sometimes the presence of iron is obvious – such as in orange, amber or golden-coloured hues in the surface of the stone, but not always. Iron begins to oxidise if it is exposed to moisture – much like rusting metal.

The presence of iron in itself isn't necessarily a problem, until it's combined with high moisture levels – such as when used outdoors or in wet areas such as bathrooms. In this case, your stone tiles may start to look yellow or, in more serious cases, brown.

Iron staining is possible in a variety of stones, but can be particularly prevalent in white marble, some types of limestone tiles and granite.

Natural stone tile turning yellow because of oxidation.Oxidation can cause your natural stone to start yellowing.

Preventing oxidation with the right stone tile finish

With oxidation, prevention is better than cure. In fact, curing the problem is extremely difficult and sometimes impossible. Some people have their natural stone tiles in place for years without any issues, while others may notice their tiles begin to yellow quite quickly. 

To ensure your natural stone tiles last as long as possible, a good-quality sealer known as an impregnator should be used. An impregnator works by penetrating the stone to create a barrier to liquid while also allowing moisture to evaporate if it does get in.

An impregnator does not protect the surface of the stone from normal wear and tear such as scratching. You may be able to apply a sealant or coating to protect the top surface of the stone, but it's important that this does not trap moisture inside.

It's worth first determining if iron is the cause of the staining.

If your tiles are already showing signs of oxidation, before embarking upon a cleaning effort, it's worth first determining if iron is the cause of the staining. Do this by enlisting the help of a professional who can test your tiles for iron content. Should you discover that the staining is a result of natural iron content, cleaning will be much more difficult because it is embedded into the stone.

Surface staining – such as that caused by improper maintenance, poor quality coatings or a build up of dirt, is more easily cleaned. You may be able to clean your stone tiles with a poultice paste and specialist chemicals available from your local supplier.

Natural stone can really make a design project, whether you're looking for a luxurious or rustic finish, indoors or out. But by knowing what protective measures you need to take before laying your stone or at regular intervals in the form of maintenance, you can save yourself a whole lot of hassle, cost, or distress.

If you'd like some expert advice about the right type of stone for your next project, or maintenance of your existing materials, contact our friendly team today.