As mentioned in prev posts, I will be laying some Black Basalt paving shortly. After more research on this site, I'm thinking of using the aforementioned for the pointing. My only thoughts are firstly am I going the right way (or should I go the tried and tested 3:1 on your knees method), and secondly will this stuff come off ok from the basalt, particularly as it has a flamed finish and I'm concerned it will get trapped in the surface.
One more thing. I will be running a single course of granite setts as an edging on one side (this then leads to lawn), how will I get the slurry to stay in the sett joints without leaking onto the lawn?