One problem we encounter a lot at Tile Doctor is damaged caused to natural stone tiles by unsuitable household cleaning products. This customer, who lives in the small West Surrey village of Churt, had done this by attempting to use Cilit Bang, which is an acidic product, to remove limescale from his fantastic Slate tiled shower cubicle. While the product may indeed remove Limescale, it does say on the label that it should not be used on natural stone.
Putting these types of products in contact with acid-sensitive stone typically results in some sort of etching, however, I had never before seen the type of damage that had occurred on these Slate tiles. At first, I thought the damage – which appeared as a sort of white staining – might simply be damage to the sealer. But when I did a test clean to remove the sealer, it became clear that the stone had suffered from very deep staining and the only way to remove it would be to use a process we call burnishing.
Burnishing an Acid-Damaged Slate Tiled Shower Cubicle
The burnishing process is a type of polishing which involves the application of diamond burnishing pads in sequence. Each pad has a different level of grit, allowing for dirt and stains to be broken down before the stone is gradually polished. We typically use burnishing on Limestone, Marble, and Travertine, but it can be used on all manner of stone in the right circumstances. This being a vertical surface, I had to complete the process using smaller six-inch pads fitted to a handheld buffer.
I started by applying the 400 grit (Coarse) pad, and followed on through to the 800 grit (Medium) and 1500 grit (Fine) pads, using a small amount of water as lubrication. I then left the tiles to dry until the next day.
When I arrived back at the property, the customer remarked that the tiles looked massively improved. Nonetheless, I found I hadn’t removed all the staining possible, so decided to repeat the burnishing process once – but this time used the pads without any lubrication. Once I was satisfied with the results, it was time to seal the tiles.
Sealing a Slate Tiled Shower Cubicle
My choice of sealer was Tile Doctor Colour Grow, which impregnates the stone to block ingrained dirt and staining. As the name of the product suggests, it also enhances the dark natural shades in the Slate, giving the shower cubicle a bold, healthy and rich appearance.
The customer was really pleased with the end result, which can be seen in the photographs above and below. So pleased was the customer, in fact, that he asked me to quote for the restoration of his Limestone tiled patio.
Source: Restoring the Appearance of Black Slate Tiles in a Surrey Shower Cubicle