sealing stone

[iamgroucho]

evening all, I've been hacking off render to reveal a couple of old fireplaces and now I'm considering hacking off all the render in the wall to have a completely exposed stone wall. But can anyone recommend what I should use to seal the stonework and lime mortar? At the moment the mortar is very dry and literally crumbles away and is very dusty. Many thanks in advance

 

[Mrs Ten Names]

For the lime mortar you could try a decent lime wash.
You can colour it with a powder pigment.
Try a small area first.