How to Clean a Slate Fireplace Hearth

Samantha Volz

Slate is a common material used in the building of fireplaces because of its resilience, durability and ability to withstand high temperatures. If you have a slate fireplace, everyone who enters the room will be drawn to the warmth and beauty of your hearth.

With all eyes on the fireplace, it's essential that you keep it clean. Thankfully, there are a few methods that can keep your slate fireplace looking beautiful and welcoming at all times.

  1. Mix one to two drops of mild dish detergent with two cups of warm water in a bowl.

  2. Soak a washrag in the cleaning solution and rub off the dirt and grime from the surface of the fireplace.

  3. Dry the fireplace with a towel or allow to air dry. Be sure the fireplace surface is completely dry before applying additional cleaners. Air drying can take several hours; consider allowing it to dry overnight.

  4. Apply a thin layer of teak oil, available at most hardware stores, to the surface of the fireplace using a soft cloth. Wash with a cleaner containing trisodium phosphate (TSP) if you do not have access to teak oil. TSP cleaners, such as Spic and Span, will break down dirt and grime without harming the slate. Follow dilution instructions on the TSP cleaning product and rub directly onto the stone using a soft cloth.

  5. Wipe down the fireplace with a cloth dampened with clean water to remove any extraneous cleaner.

  6. Apply furniture polish to the slate with a soft cloth for extra shine. Rub into place and buff dry.

  7. Tip

    Even if it does not appear dirty, clean you slate fireplace every two to three months to prevent staining or the need for a large-scale cleaning. If you do not have access to teak oil, use olive oil as a quick fix. However, cleaning a fireplace with olive oil multiple times may result in a foul smell caused by the oil reacting to the heat from the fireplace. Slate cleaning oil is available for purchase from stone manufacturers. This works in the same way as the teak oil.


    Spot test any cleaning solution on an extra piece of slate or an inconspicuous area of the fireplace to be sure that the cleaner will not harm the slate.

    Never use a wax product on your slate fireplace because it will melt with the heat of the fireplace and stain the slate.