Some types of natural stone can acquire rust stains. In fact, it’s one of its biggest nemeses of natural stone. This is due to the chemical composition, rust composition, and molecular structure of the hardscape material.

For instance, when you notice rust-like colours or veins on your light STONEarch stone product, it’s very likely that there’s an iron deposit present in the stone. Natural stone is quarried in large blocks and cut into sizes to make pavers, flagstone, copings and steps. In our refining process, our factories are diligent to discard any material that shows signs of oxidation. With that said, sometimes the iron deposits are not on the surface but instead found underneath a few layers of the stone.

Sometimes, it will take years of wear and tear for this iron deposit to rear its ugly head on the surface. In most cases, it will never even be noticeable or reach the surface. Therefore, rust is a rare and uncommon problem in the natural stones that we carry. Also, our world-class quarries and inspection teams work to ensure none of the products that we sell will face this problem. However, stone is a natural material, meaning it is sometimes impossible to detect if a large iron deposit is present within it, causing rust to appear on its surface.

What Are The Different Causes Of Rust Stains In Natural Stones?

Discolouration can occur on some STONEarch stones like sandstone because of the oxidation of their natural iron content. This chemical process can cause your stones to have brown marks. However, darker granites like our Gray, Onyx Black, and New Ebony, are not prone to problems related to rust.

Moreover, another common cause of rust in stones is the overusing of hydrochloric acid, which is one of the ingredients you can find in patio or brick cleaners. Hence, you need to avoid using these kinds of products on your natural stones as much as possible.

Using weed and lawn feed products can also cause your stones to have small, brown rust stains. The reason for this is because these products contain ferrous sulfate, which causes the marks. So make sure not to leave any pellets on the surface of your stone. Additionally, running rusty water off your steel or iron tools that are rusting can also cause rust on your stones.

Leaving behind a metal wrench on your stone patio over the course of the winter can cause the metal to rust and leave a stain on your natural stone pavers as well. However, this can usually be cleaned fairly easily but it may depend on the type of stone.

How To Prevent Rust In Natural Stone

One of the best ways to prevent rust on natural stone is to protect your investment before it occurs. This means using a preventative measure which is to use a sealer to protect the surface of your natural stone in your outdoor kitchen, pool deck, or outdoor living space.

Sealing your landscape stone can help lock in its surface layer, preventing corrosion from the inside. This means that the only thing you have to take care of is rust stains on the surface, which is pretty simple to get rid of.

How To Remove Rust Stains On The Surface

The visible rust stains on your natural stone are most likely surface stains if your stones have a new sealing. You can easily remove these using a scouring pad or a soft nylon brush.

If your stones have a strong seal, it will not let oxidized liquids to seep through its pores. Hence, you’ll be able to remove those surface stains with ease. But to make sure your beautiful stones are safe, it’s a good idea to apply a fresh coat of sealant when you’re done removing the rusts and all other surface stains.

How To Deal With Stubborn Rust

Sometimes, you won’t be able to remove the rust on your stone’s surfaces no matter how hard you scrub them. You may need to call the help of a professional if the rust stains appear to be floating just under the surface.

Nonetheless, you may want to try the following steps first:

• Pour or spray 3% to 4% hydrogen peroxide over the area with rust stains.
• Use a nylon brush or a cleaning pad safe to use on natural stones to agitate the solution.
• Let it sit for at least 24 hours, and then rinse afterward.

If the stain is still present, then consider calling an expert to fix your rust problem. Remember to try these solutions first on an edge or corner of your stone patio. Some chemicals have adverse reactions to certain types of natural stones, so it’s important to test a solution first on an outer edge before using it in the middle of your stone walkway.

What To Avoid Using When Dealing With Rust

There are plenty of DIYs online on how to get rid of rust on your natural stone using acidic substances and common household cleaners. It’s tempting to simply apply vinegar or lemon juice to the stain like you would on other landscape materials.

However, doing so may just make the problem worse. The same is true when using metallic pads for scrubbing or steel wool. Therefore, make sure to never use any acidic substance or abrasive material when taking care of rust on natural stone.

If you have any questions on how to maintain your STONEarch natural stone, contact our support team at any time. We’ll make sure to answer any questions you have in mind with the best of our knowledge, and as soon as possible.

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