limestone colour advice - Tile Advice

[MariaG]

Hello We had limestone tiles installed and,at the time, the tiler said he had run out but not to worry he had some spare in his van. The two tiles he put in are noticeably different (darker) than the rest. Last week we had a damp mat on the tiles next to it and when we moved the mat the tiles underneath were the same colour as the two that are different. They change d back after they dried. Is there something we can use on our tiles to make them look the colour they turned to with a wet mat on them so they all look the same? I hope this makes sense

 

[Dave]

Colour intensifier.