limestone floor water damage

[Barbel Bob]

Hi all,

I have a very old polished limestone floor that has recently been water damaged, there is a fine white powdery substance laying on the floors as it is drying out which i just sweep away. Once dried out what would be the correct way to restore it? and what products are available in France for this? would i need to hire a buffer machine to finish off with a polish??? [8-)]

Thanks

J