Is an F-G diamond good

'Good' is a judgement and you are the judge.

The colour ranking of a white diamond of F-G is a step or two below 'colourless'. This means that the inclusion of nitrogen, which gives diamond a yellow cast, is minimal. A step or two above this rating means that the inclusion of nitrogen is non-existent.

To the non-gemologist, to the naked eye, this colour ranking is imperceptible.