As a follow up to our last Care Tip on How to Visually Identify Your Stone, you can run a couple of tests to chemically identify your stone as well. If you have a sample or extra tile of the stone, and you can’t quite identify it visually, you can do some testing to help confirm the type of stone you have. By doing so, you can determine the best way possible to maintain its natural beauty.
Marble and limestone contain calcium that is very sensitive to acids, but granite does not have the same sensitivity. If a drop of acid is placed on the stone and it begins to bubble, it is marble or limestone. Marble will generally react stronger than limestone, while granite will not react or etch at all. Common household acids you can use for testing are soft drinks, orange juice, lemon juice and vinegar. Place a drop of acid on your stone, wipe off after 1 minute, then check for etching (a dull or rough spot on your stone). If the test stone etches, you will need to make sure to wipe spills immediately and keep your stone sealed as acids can remove the top layer of your stone, leaving a dull mark behind.
Absorbency is also an important factor to consider. Place a few drops of cooking oil on your stone sample. If the surface turns dark almost immediately, you will need to take great care to wipe any spills quickly because your stone is highly absorbent and will stain easily. If you notice that the oil takes some time to absorb (a half a minute or more), then you have a stone whose absorbency can be effectively controlled with a quality impregnating sealer.
Stones also have varying degrees of hardness. Since granite is difficult to scratch, if a knife or razor blade edge is run across the surface it will not scratch while marble and limestone will. If the test stone scratches, try using trivets, coasters and felt pads on the bottom of anything that slides on the stone to help avoid scratching.
For additional care tips for your marble, granite, travertine, terrazzo or other natural stone and grout, please visit our Care Tips page! If you have additional questions or would like to schedule a free estimate with one of our stone care experts, please contact us today!