A metamorphic stone that is formed in layers, slate differs greatly from many other stones in both looks and performance. While other metamorphic stones, such as marble, are prone to staining and absorbing moisture, slate is relatively non-porous and performs well under the water and lemon juice test with little staining or etching.
Slate’s natural cleft and honed finishes, however, do scratch fairly easily. Whether it’s a chair dragged over a floor, or a knife used on a counter, scratches on the slate show up as white lines and marks that do not disappear when wiped with a cloth or soap and water.
These scratches dull and take away from the beauty of the stone, but they can be very easily removed or disguised so that they are less noticeable.
Some scratches on natural cleft slates can be buffed out using scouring pads of progressively fine texture. It’s important when using this method to work wet, and to make sure not to work over too large an area, or the repair may become more visible than the original scratch.
If there are scratches covering large areas of the slate, they can be hidden and helped to blend in with the rest of the stone by deepening the color of the scratch. To do this, use either a color enhancing topical sealant or apply mineral oil to the stone. Both will darken and deepen the color of the slate, while at the same time blending the scratches into the surface so they are invisible to the naked eye.
Color enhancing sealers do not wash off with neutral soaps and waters, and can be reapplied as needed or on a yearly basis. They will also help to protect the stone from future damage and help render it more slip resistant.
Scratches are very common on slate floors and counters. Remove them or hide them using these methods to preserve the beauty of the stone.