Gallery 77 is the greater Hudson, WI area’s full-service solution to natural stone countertop and tile maintenance. Call (715) 808-8232 today for a discount on our first resealing service!

Pores. They aren’t just of interest to dermatologists. They also exist on the surface of natural stone – and they’re the reason why natural stone countertops and tiles require regular resealing. 

Pores are microscopic holes that naturally occur in stone. Engineered quartz, which is composed of resin and silica, doesn’t contain pores, but marble, granite, onyx and limestone all have them. Unless its pores are protected, natural stone can absorb acidic liquids such as wine, coffee, vinegar, tomato sauce, fruit juice and cleaning products. 

When acidic substances infiltrate and remain inside pores, they trigger a chemical reaction called “acid etching.” It causes the calcium carbonate inside natural stone to break down, become weaker, and permanently exhibit dull or dark-colored spots. In other words, an acid-etched natural stone surface is more likely to chip and lose its lustrous sheen.


How Do You Prevent Acid Etching?

The answer is simple: sealing and resealing.

Stone sealers are usually made of acrylic, polyurethane or natural wax. Whichever active ingredient it contains, sealer permeates any pores it comes into contact with and quite literally seals them up. In addition to acidic substances, sealer can protect against other sources of damage such as heat and moisture.

Sealer isn’t a magical shield against damage. It is still important to wipe up spills as soon as they occur, as well as use trivets to minimize natural stone’s exposure to heat.

Sealer also isn’t a permanent solution. The abrasion caused by everyday wear and tear gradually lifts sealer away, which is why regular reapplication is requisite to preserve the integrity and appearance of natural stone.

Quartz, soapstone and silestone are usually nonporous enough to go without regular sealing. Other types of stone vary in porosity, and accordingly require resealing at different intervals. Depending on how frequently they are used, granite and marble surfaces require resealing every six to 12 months. Less porous quartzite and slate both fare well with annual resealing. Limestone usually needs resealing every two years, whereas travertine and onyx can both last up to three years before they require treatment.

How Do You Know When Natural Stone Needs Resealing?

Do the water drop test: sprinkle water on the stone’s surface, and leave it for 15 minutes. If the stone appears darker or absorbs the water in less than four minutes, then it is time to reseal it.


How Do You Reseal Natural Stone?

The process for resealing natural stone is straightforward. Any DIYer can do it without too much time or effort!

  1. Clean stone. Wiping down the surface with a pH-neutral cleaning product and lint-free cloth promotes more uniform application of the sealant. It also prevents the sealant from permanently locking in existing stains.
  2. Ventilate area. The majority of sealers aren’t toxic, but it never hurts to minimize your exposure to chemicals. Turn on a fan and open a window before uncapping your sealer. Wear gloves as well.
  3. Test sealer. Apply a very small amount of sealer to a less visible part of the tile or countertop. If it discolors the stone or creates a cloudy residue, then you have chosen an unsuitable product for your natural stone.
  4. Apply sealer. Follow the sealer manufacturer’s application instructions to the letter. Note that curing (i.e. drying) time varies depending on the product. Most sealers are usually dry to the touch after four hours. Even so, penetrating sealers and topical sealers typically take 24 to 48 hours to fully cure, respectively.
  5. Reapply sealer. Additional sealing can only provide even greater protection against acid etching, and is especially advisable for highly porous natural stone surfaces. Wait 15 to 30 minutes before applying a subsequent coat.
  6. Remove sealer. The surface you’re sealing will not absorb 100% of the product. Wipe off excess sealer using a microfiber cloth to prevent discoloration.

Hire Gallery 77 for All Your Resealing Needs

Maybe you aren’t confident enough in your DIY skills to feel comfortable resealing your valuable countertop. Or maybe you’re simply too busy to allot the time that quality resealing demands.If you live in the greater Hudson, WI area, then you don’t have a problem. Our services extend beyond fabrication and installation. We also provide the regular resealing and other maintenance you need to keep your natural stone surfaces beautiful and fully protected! We welcome you to contact us today to schedule service at your home or place of business