Water stains on newly blasted internal flags

[Nlomax]

Hi

I've just had internal ground floor of haslingden flags ( granite-hard sandstone) sandblasted. ... Not sealed yet but now have water marks on some of them. Some circular and ringed but one large area seem rust stained at outer edges. Any advice on getting rid? Grout cleaner has been suggested.....

Thanks in advance

[GB_Groundworks]

Photos would help there's a sticky on the main page about posting them if not email me the photos and I'll post them up