How to choose, how to calculate a container, how to compare stone.
Sesame White (G603) is a pale base with fine grey dots; Sesame Grey (G602) is a mid-grey base with distinct black and white grain. This is a difference in base colour, not the same stone at two depths. Choose white for brightness and low contrast, grey for dirt tolerance and paving.
Bottom line: Sesame Black (G654) has a near-black base with fine grain; Sesame Grey (G602) has a mid-grey base with coarser, more visible grain. Both work outdoors. Black suits dark facades and worktops, grey suits large bright paving. Judge colour first, finish second, price last.
Why G603 works on a worktop, and the two details that decide whether the job fails.