- Reaction score
- 21
Limestone is mainly composed of Calcium Carbonate which has a pH of nearly 10 which makes it towards the high end of alkaline (14 being the maximum). Even weak acid solutions will cause a dissolving action, and even something like cola which is acidic can dissolve and stain the surface. Without an impregnating sealer, limestone remains vulnerable to any weak acid solutions over time (including acid rain in areas of high pollution).
