It would be wonderful if everyone who sold granite was ethical, truthful and fully informed about every type of stone they sell. Unfortunately, thousands of different types of stones are on the market today, and obtaining reliable information about each is difficult.
Myth: “Granite is heat resistant, so it is perfectly okay to place hot pots on a granite countertop.”
Bust: While it’s true that granite is quite resistant to the sorts of temperatures encountered in kitchens, excessive heat can damage or discolor some types of granite sealers. Rapid heating can also generate internal stresses that could cause a crack at a weak spot, such as a natural flaw or fissure in the stone. Using a hot plate is an easy way to eliminate potential problems.
Myth: “Granite countertops won’t chip, crack, or stain.”
Bust: High-quality types of granite are very resistant to such damage, but any stone will chip if a hard, heavy object hits a square outside corner. Cracking may result from natural flaws in the stone or errors in fabrication or installation. Some stones sold as “granite” will absorb cooking oils, which darkens those areas significantly. Other stones containing calcium can be etched and whitened by acidic liquids such as citrus juices or vinegar. These stones are sometimes marketed as “granite,” but may actually be marble or limestone. True granites are not subject to acid etching.
Myth: “Granite countertops should be resealed once or twice a year.”
Bust: This is a generalization. Many different types of stone are sold commercially as “granite.” Some are inherently resistant to staining without applying any sealer. Applying sealers to these stones can actually cause other problems. For example, high-quality black stones usually do not need sealers. On the other hand, some stones sold as “granite” are so porous that their shortcomings can’t be solved by even the best sealers. There is no single recommendation that can be made about use of sealers on granite. The answer is specific to each individual type of stone.