Mortar dye - Mortar dye

[daza1001]

Hello Lads,
What is the best mortar dye liquid or powder, in black. Need to match slate grey concrete coping stones the best I can.
Any tip appreciated as not really used dye that much before except on ridge tiles.
Thanks

[lutonlagerlout]

all mortar dyes will be a light grey in 6 months time
the only sure fire way is to use basalt sand £££
LLL

[daza1001]

all mortar dyes will be a light grey in 6 months time
the only sure fire way is to use basalt sand £££
LLL

Thanks

[joydivision]

LLL is spot on. Off the shelf dye's fade rapidly, also work out expensive if achieving a deep colour.
We use Tarmac's lime sand with added synthetic iron oxide pigments.

JD