Our design team suggest you use Grout Colour 02 Warm White for a contrasting look.
Or for Grout colour 05 Shadow to highlight.
Or grout colour 11 Anthracite to blend.
Recommended Grout Joints - (We have assumed that your substrate has a perfectly flat and plumb surface, please check with your tiler.)
4mm grout joint. Based on this joint size, 1 bag of grout would cover 2m².