Natural stone can be classified into two general categories according to it's composition: siliceous stone or calcareous stone. Knowing the difference is critical when selecting cleaning products.
Siliceous stone is composed mainly of silica or quartz-like particles. It tends to be very durable and relatively easy to clean with mild acidic cleaning solutions. Types of siliceous stone include granite, slate, sandstone, quartzite, brownstone and bluestone.
Calcareous stone is composed mainly of calcium carbonate. It is sensitive to acidic cleaning products and frequently requires different cleaning procedures than siliceous stone. Types of calcareous stone include marble, travertine, limestone and onyx. What may work on siliceous stone may not be suitable on calcareous surfaces.
How to tell the difference
A simple acid sensitivity test can be performed to determine whether a stone is calcareous or siliceous. You will need about 4oz of a 10% solution of muriatic acid and an eyedropper. Or you can use household vinegar and an eye dropper. Because this test may permanently etch the stone, select an out of the way area (a corner closet) and several inches away from the mortar joint. Apply a few drops of the acid solution to the stone surface on an area about the size of a quarter. If the stone is calcareous, the acid drops will begin to bubble or fizz vigorously. If little or no reaction occurs,the stone can be considered siliceous. Rinse the area thoroughly with clean water and wipe dry. This test may not be effective if surface sealers or liquid polishes have been applied. If and old sealer is present, ship a small piece of stone away and apply the acid solution to the fractured surface.
If you have any questions about this article please call us at 403-526-4821.
No comments:
Post a Comment