Think now about the colour of your rock. How dark is it?:
More help with this question:
Rocks come in a multitude of colours, for simplicity we have divided them into three catgories:
Dark coloured rocks: may be black, dark brown, dark grey or dark green.
Intermediate coloured rocks: are pale grey, reddish brown or green.
Light coloured rocks: are pale pink, pale green, light grey or white.
Tip: the colour of a rock can also be influenced by its grain size. Very fine grained rocks often appear much darker than their coarse grained or coarsely crystalline equivalents.