Posted: Sun Apr 11, 2010 5:51 pm
Hi guys anyone got experience of a black residue leaching out of Indian Sandstone? its has a slightly oily texture and has been happening now for 12 month, some flags that had it are now clear some that were fine are just starting to discolour, most strange! ive laid thousands of meters of stone n never seen anything like this, they are laid on a full mortar bed and wet mortar pointed just as i always do. I really dont want to have to re do the job again, any ideas? Cheers Chris