New slate - Removal of marks on new slate

[Toby Woods]

Hi

I have just laid a new 40sqm black to blue slate patio with slate purchased from Nustone.
The patio looks great but after cleaning away all the white dust on the slate I have noticed lots of marks on the slate (water marks?).
I have tried to clean them using water and a scrubbing brush but am unable to remove the marks.
I have not yet sealed the slate and am worried to do so as once sealed the marks may be almost impossible to remove.
Can you please advise what is the best way to remove the marks from the new untreat slate.

Thanks
Craig

[London Stone Paving]

I know the marks that you mean
Unfortunately they are part of the stone and you will not be able to remove them.
Out of interest, why are you sealing slate?
Steve

[Toby Woods]

We want the slate to have a darker appearances so was hoping to get this with a sealer.

[Tony McC]

Slate is not an easy stone to seal because it is relatively impermeable, so any sealant/colour enhancer tends to sit sulking on the surface rather than impregnating.

There are specialist sealants for such materials, so if you really must seal, make sure it's a suitable product and not one designed for porous stone such as sandstone.

Some suggestions

[Toby Woods]

Hi
Thanks for your great replys.
I am looking at using some "Larsen Impregnating Sealer".
It says that is it designed fro slate, do you rate this product?
http://www.nustone.co.uk/accesso....re.html

[Tony McC]

Never tried it on slate, so I can't really say.