stone floor

[jagre]

Hi
I live in an old victorian house with an original yorkstone floor in the living room. The floor has been covered with a silicone sealant and we are looking to get it off and clean it up. Our decorator bloke has tried sanding it, tried petrol (!) and paint stripper etc all to no avail. If anyone has any ideas it would be appreciated. We have been told to use a nail or needle gun thoughts???