Why Does My Granite Countertop Change Color When Wet?

Granite countertops appear in millions of kitchens, bathrooms, and laundry rooms throughout the United States. Counters in all different colors, ranging from one end of the color spectrum to another. With specific countertop colors, you may notice discoloration when the counter is wet. There’s usually a single culprit, and we’re here to unveil it, so stick around to learn more. 

What Causes Discoloration On Granite Countertops?

Usually, the cause of the discoloration on your granite countertops is water or any other liquid. With lighter-colored countertops, there’s a better chance you’ll notice the discoloration, as darker stones hide the inconsistencies better. 

Granite is a porous stone, so the surface of the stone allows water and other liquids to cling to it and absorb. The absorption darkens the surface, creating color inconsistency. Even if the countertop seems extremely smooth to the touch, there are uneven areas and holes throughout the surface on a microscopic level. This allows liquids to seep in and take hold. 

For the most part, liquids spilled on your countertop will evaporate within the hour. Once it evaporates, the slight imperfection will be gone. However, colored liquids like wine, coffee, bright fruit juices, and soy sauce can stain your countertop. 

How Do You Fix Discolored Granite?

Dishwashing Soap

In some cases, you might not catch the spill quick enough to prevent a stain. But, no worries, you should be able to remove it with a homemade solution. If there’s a stain on your granite countertop, here’s what you’ll need:

  • Dishwashing soap (for oil stains)
  • Hydrogen peroxide-based cleaning spray (for other types, like coffee, tea, etc.)
  • Baking soda
  • Hydrogen peroxide
  • Clean cloths
  • Plastic wrap
  • Masking tape
  • Plastic or wooden scraper

For an oil-based stain, use grease-lifting dish soap. Apply diluted soap to the stain with a soft cloth. For other types of stains, use a hydrogen peroxide-based cleaning spray. Although gentler cleaners are usually better for granite, tough stains may require hydrogen peroxide. 

Once the area is cleaned, treat the stain with a poultice paste. For oil-based stains, mix baking soda and water until it is about as thick as peanut butter. For other stains, mix baking soda and peroxide to the same consistency. 

Cover the area with plastic wrap, then secure it with masking tape. Poke a few holes in the plastic, then let it sit for 24 hours. 

After a full 24 hours, remove the plastic and scrape away the residue with a plastic or wooden scraper. Rinse the surface with distilled water and polish the stone with a clean cloth. 

How Can You Tell If Granite Is Sealed?

Spill on Counter

Sealing your granite helps ward off unwanted stains on the surface. Depending on how frequently you use your countertops, you may need to complete the process several times per year. 

Some homeowners may only need to seal their granite counters once every year or so, it just depends on how heavily you use the counters. Although sealant doesn’t protect from etching, it wards away stains, particularly from darker-colored liquids. 

If you have hard water in your house, it’s a good idea to seal the countertops more often. Water with high mineral content can react with the stone and change its color permanently. It’s best to stay on top of sealing your countertops to avoid deep-set, stubborn stains. 

You can easily tell if your granite is sealed or needs to be sealed using the water test. Here’s what you’ll need to complete the test:

  • Water
  • Dry cloth

Simply pour about a tablespoon of regular tap water onto the counter’s surface and let it sit for about ten minutes. 

Wipe away excess water with a dry cloth. If the stone is darker than its surroundings, your counters need to be sealed. If the color remains the same, the stone is sealed. Generally, if you notice short-term contact with water darkens the stone, it’s time to reseal the stone. 

Absorption Rates

If you know the origin and type of granite composing your counters, you can look up its “absorption rating” online. Generally, stones with less than .25 percent absorption don’t require sealing.

However, it’s never a bad idea to double-check with the water test. Better to be on the safe side with beautiful granite than skip the sealant and end up with discoloration. The more quickly and drastically the stone changes in the test, the more porous the surface is.

If the color of the stone remains the same after the water test, the sealant isn’t necessary. Sometimes, the stone is already sealed. Other times, the stone may have an extremely low absorption rate, preventing it from absorbing water. If you apply a sealant to these countertops, you could make your granite look cloudy, hiding the clarity of the natural stone.  

Is It Hard To Reseal Granite Counters?

Granite Gold Water-Based Sealing to Preserve and Protect Granite, Marble, Travertine, Natural Stone Countertops-Made in the USA, 24 Fl Oz (Pack of 1)

No, resealing granite countertops isn’t tricky. If you’re comfortable tackling the project, it’s a reasonably easy DIY process. Many homeowners seal their own granite countertops without an issue. If you decide to seal the surface yourself, make sure you use a granite sealer specifically designed for such. 

Of course, if you don’t have the time to complete the project or aren’t comfortable doing so, you can hire a professional to reseal the countertops for you.

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