Hi LLL
Thanks for the reply.
No it was silver sand to go with white cement for the laying course - light coloured sandstone.
Found Cornwhaul who could supply [nation wide] silver granite sand (4-0) and grit (6-2).
After reading about the advantages of permeable laying course, decided to go with the grit.
Just hope I'm up the greater challenge of using this as I've never done this before.
Another question while you are on - could you recommend a quality SBR to mix with the white cement for the bond bridge.
Cheers
AliP