O
Olz
Ask him to lend you his, im not convinced, the products dave has suggested are the way to go in my opinion, I really hope you manage to get it sorted mate, it would be tragic if that was ruined after your hard work.
View all of the UK tiling forum threads, questions and discussions here.
LTP is the brand I use, check it out herehi there.
i have a similar issue, although nowhere near as badly stained.
going to try the products Dave suggested (how did you get on with those btw?)
also wondered if anyone could recommend a good sealer for black limestone - there are plenty on offer but i'm sure some are much better than others.
thanks..