Natural stone is a beautiful, rustic addition to any patio space, but while stone is durable and can last for ages, it is also porous and susceptible to staining and damage, unless maintained properly.
Normal wear and tear, even the acidic compounds found in many food and drinks – especially those we love to eat outdoors during BBQ season – can cause permanent damage to stone. First and foremost, the best thing you can do to ensure the life of natural stone is to seal it. A good quality sealer will protect your stone top from moisture penetration and staining, though over time even the best products will lose their protective capabilities, and expose the stone to potential stains and scratches.
To clean your stone tops and prevent debris from settling in and leaving stains or discolorations, you can simply rinse off your table top with clear water. After rinsing, use a mild detergent mixed with water and scrub the table top with a soft, clean cloth or sponge, one that won't bleed color. Be sure to dry the stone thoroughly after cleaning to prevent any moisture penetration. Spills should be cleaned up reasonably quickly, since over time any liquid may begin to penetrate the sealant.
If your top requires a more thorough cleaning, opt for a pH neutral product. Avoid ammonia based cleaners which can break down the sealant and possibly damage or discolor stone. You should never use scouring creams, abrasive cleanser or acid based products like those that include citrus, pine or vinegar among their ingredients. Also, don't use alkaline based products – those that include ammonia, baking soda or borax – unless they are specifically formulated for use on natural stone or marble.
Most high quality stone tabletops are coated with a stone enhancing sealer that provides extraordinary resistance from stains and moisture, and will help maintain the stone's natural color. For optimum protection, plan to reseal your tabletop every 6 to 12 months after you've thoroughly cleaned it of debris and dirt.
Though built to withstand the elements, if you want to keep your stone tops looking beautiful for years to come, consider storing them when they aren't in use. In cold climates, we recommend storage or at least covering them with suitable outdoor furniture covers. Try to keep the cover from touching the table top itself, to promote airflow and allow moisture to escape. Snow that is left to sit on an uncovered table top for any extended period of time may cause moisture to penetrate the sealant, which can cause the stone to crack. Always seal the tabletop before each winter.
In hot climates, the porous nature of stone leaves it susceptible to heat retention. Exercise caution when handling stone that has been in direct sunlight for any period of time.