Granite is very resistant to most acids and will not etch or leave a dull spot on the surface. It will not scratch as easily as marble. However, Hydroflouric acids found in products such as rust removers will mar it's surface and should be avoided.

Granite can be cleaned with ordinary window cleaner as often as you like.

Natural stone surfaces need to be sealed when they are new and then resealed on a regular basis depending on the softness of the material, (Usually, at least annually).

Our Mohs Hardness Scale shows the hardness (or softness) of many natural stones. Remember that even though your countertop is made of 'rock hard' material, it is not as hard as you would think and can be damaged by many different elements. Both Marble and Granite can be broken down in their natural state by weathering or erosion, so it is easy to understand how acidic foods and harsh chemicals can affect your finished countertop.

Marble Composition:

Marble is an example of a rock that may be formed by contact metamorphism.
Contact metamorphism occurs when rocks undergo metamorphism because they come in contact with a heat source (usually a magma body). Essentially the rocks are getting cooked. A comparable change occurs in roasting meat or baking bread - the initial composition does not change but the texture of the material does.
Marble forms when Limestone is heated to high temperatures.
Both Marble and Limestone may have the same composition but marble typically has larger grains and is composed largely of Calcite.

If Marble is sealed properly it can be cleaned with warm water and a non-abrasive cloth.

Marble is relatively soft when compared to other stones such as granite. It will scratch very easily. Marble is also very sensitive to acidic chemicals such as vinegar which will leave a dull spot on its finish. Most household products that contain acids will have their ingredients listed on the bottle label. Avoid using any of the following on or near any marble surface:

• Vinegar
• Lemon or other Citrus Juices.
• Tomato and Tomato Sauce
• Bleach
• Coffee
• Body fluids such as urine, vomit
• Ammonia
• Tile cleaners
• Toilet bowl cleaners
• Household cleaners with Lemon
• Pool Ph degreaser (Muriatic Acid)

There are good sealants available at most retail home supply stores. Make sure you follow the instructions on the sealant container for application and recommended frequency for follow-up use.