1. I have a natural limestone tile on my kitchen floor can I use this? We do not recommend to use on natural stone as it can react with natural minerals in stone. Natural stone normally has good slip resistant properties so we would suggest a good deep clean with our Stain Proof Alkaline Cleaner. This will clean and bring back the natural slip resistance of the stone tile. 2. How long will this treatment last? This is a permanent solution as it etchs the surface of the tile putting microscopic pits into the surface creating coefficient of friction under foot. We recommend to use our Stontex Heavy Duty Grime Remover as a general maintenance cleaner to ensure these pits are clean and open, thereby ensuring the slip resistance of the tile is not compromised.   For help and advice Ask the Doctor: https://stonedoctors.ie/ask-the-doctor/