It is essential that you understand which stones can be treated with acidic products in order to remove rust and which cannot. Please read the following and contact us if you have any queries. Always do small test areas first. Read all product instructions. This is YOUR responsibility.
Understanding Iron Oxide (Rust) Staining
Some stones such as granite, slate and sandstones can become discoloured due to a natural iron content oxidising (Rusting). This can cause brown marks or, in the case of grey or black granite, dark patches.
A common cause of this issue being rapid and / or severe is the use of hydrochloric acid contained in brick and patio cleaners. Never use these products on natural stone.
Another common cause of small, brown rust marks is the use of lawn feed and weed type products. These contain ferrous sulphate which can cause marks; do not leave the pellets on your stone!
Rust marks can also be caused by rusty water running off iron or steel tools, furniture or fixtures that are rusting.
On acid resistant stones such as most sandstone, most granite and most slate where the staining is not too severe, use Builderase. In additon to reading all of the instructions on the product page, the following guidance will help you:
If the staining is severe on the above, acid resistant stones, and Builderase is not working well enough you can pre-treat with Gel Rust first.
For Rust Marks on acid sensitive stones such as limestone, marble and travertine and all cement based surfaces you can use Gel Rust.
Do NOT use Builderase on acid sensitive stones.
For all instances of rust staining, DO A DEMO AREA FIRST.
If you require additional assistance, please contact us.
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