It has a natural water resistance that helps protect it. However, it isn't water-proof. Because granite is a stone, it is also naturally porous. And while it won't absorb in the same way as, say, sandstone or limestone, it will still absorb bits of moisture that can eventually damage your counters.
Most water stains are only a temporary problem. The granite may darken or lighten in color when the water is absorbed into the stone. However, once the water evaporates, the color of the stone should return to normal. You need to seal the surface regularly with a high-quality sealant, which prevents water absorption.
Again, you can make a paste with baking soda and water. For a poultice to work, however, you need to apply it to the affected area, cover it with plastic wrap (you can tape down the edges if needed) and let it sit for 24 hours. Wipe or scrub the poultice away, and reapply as needed to remove hard water stains.
While granite is a notoriously hard stone and renowned for its resistance to damage, it can indeed be stained; in fact, all natural stones can be stained if not properly cared for. However, most water stains on your granite countertop will only be temporary — if you act quickly and take the right steps.
If the Stains Are Still Visible, Apply the Paste Again and Let It Sit for 24 Hours. Even granite countertops are not immune from hard water stains, which can create unsightly blemishes along the stone. Follow these steps to remove such stains and restore your countertops to their former glory.
Make a paste of baking soda and water, or talc with a diluted solution of ammonia, bleach, or hydrogen peroxide. Use a soft brush to scrub the stain with the paste and then rinse it thoroughly. If you're getting results from this procedure, repeat it until you're satisfied with the progress.
Removing water stains from granite typically involves the use of a poultice. This is a solution that can be created by a mixture of baking soda and 3 percent hydrogen peroxide. Mix these ingredients in a bowl until it forms a thick paste. Once this happens, apply the solution to the stain.
The water soaks into the stone, but it can't go very far. Thus, it will eventually evaporate. Unfortunately, it will leave behind any impurities that may have been present in the water.
Be sure the surface is clean and completely dry before sealing. Typically it takes about 12 hours for granite to dry prior to applying sealer. This is assuming normal, room temperature drying methods. Optimal sealing conditions are at or above room temperature.
However, vinegar should never be used on your granite countertops. Vinegar is made up of acids that can severely harm your granite. Even if it is diluted, vinegar may still leave acids on your granite countertops. This can cause your natural stone countertops to etch.
The porous surface of stone allows water to cling to it and absorb, darkening the appearance. Usually, liquids that have been spilled on your countertop will evaporate within half an hour, so even if you have very porous granite, spilling something like water or oil isn't going to permanently damage your counter.
The standard requirement for water absorption in granite, for example, is . 4 percent, while marble is . 2 percent. It's important to note that the absorption capacity of each type of dimension stone is actually a range, rather than one number.
You might need a polishing powder. Buy a polishing powder designed for natural stone countertops. You'll generally have to mix the powder with water to form a paste. Then “polish” problem areas with a soft cloth.
Granite is impervious to water, but the polished surface may be exposing one or more of these minerals that can oxidize and change color when exposed to water. Granite and marble can also be etched slightly by mild acidic fruits and juices or discolored from a hot pan set out on the counter to cool.
Steps to Fix the Discoloration:
Apply a small amount of baby oil to a clean white rag. Rub it over the lighter spot (or a portion thereof). If your countertops are not properly sealed, the oil may stain. If the oil darkens the counter and you like the look, use Stone Color Enhancer to make it permanent.
The granite erodes very slowly at only one inch every 10,000 years, while the mica schist is eroded relatively quickly into canyons and gullies. Water is the main erosive force threatening to make any real change to the mountain.
It's not much but because of the porosity, the tiny holes that are not visible to the naked eye can absorb water. Sealed granite countertops are much less likely to absorb water, however if water is left on your countertop for long periods of time, it can cause a darker spot.
Typically, granite should be resealed every 12 to 18 months. Nevertheless, there are some other factors that come into play when determining how often to reseal granite countertops. For example, a lighter colored granite will need to be resealed more often because it is typically more porous.
Just like every other countertop, quartz is vulnerable to stains, including water stains. If not taken care of properly, they can cause severe damage to quartz countertops. It is essential to take the time to remove hard water stains as soon as they occur.
One question that comes up a lot when working with granite countertops is “Does granite need to be sealed?” The answer is very simply “Yes.” Certain stones, like granite and many other natural stones, are porous. This means that a sealant needs to be applied to prevent staining from water, oils, and other liquids.
While a cloudy film on your granite countertops can be alarming and annoying, it's a very common occurrence in natural stone countertops. A cloudy film is mostly caused by a build-up of substances on the top layer of porous stone but can also be caused by poor sealing methods and by using the wrong cleaners.
The minerals in hard water cause a different kind of stain on granite. When hard water sits on a granite surface and dries, it leaves a visible mineral deposit that often creates white rings, especially around faucets.
Bar Keepers Friend Granite & Stone Cleaner & Polish is specially formulated for use on smooth, polished stone – including granite, marble, and quartz. Its pH-balanced formula won't scratch or mar stone finishes, and it's gentle enough to use every day.