Is there any way to get cement/mortar marks off indian sandstone paving?

[JohnDoe123]

Hi,

I bought some reclaimed indian sandstone paving and realised that the previous owners had laid the slabs the wrong way! So now the correct face has mortar marks round it. See photos.

Is there any way to remove the marks without it looking as obvious as it does now? What's the best way to do it without damaging the flag please?

This is a dry lay showing both sides of the slabs (on the left is the dark 'wrong' side)

This shows the marks of mortar and cement on the 'correct' side of slabs. As you can see the edges have the mortar lines on them

 

[ktuludays]

You could try some brick acid

 

[JohnDoe123]

Yeah, I think I'm going to try that even though it looks like the acid is not good for sandstone but I will use it on a spare slab to see what it does