Fancy coloured diamonds are very rare and very beautiful! They come in all sorts of colours such as yellow, champagne, cognac, green, pink, blue, red, violet, grey, black, orange, etc. Their colour is graded with a different scale unlike the D-Z for white colourless diamonds.

When describing the colour, there you have to take in consideration the strength of the colour, followed by the secondary colour and lastly the primary colour, e.g. Fancy Vivid Brownish Yellow.

Strength of colour is graded by the GIA  such as Fancy Light, Fancy, Fancy Intense, Fancy Deep, Fancy Vivid or Fancy Dark, which describes the combined effect of tone and saturation. To read more about this you can go to http://www.gia.edu/lab-reports-services/diamonds/diamond-reports/index.html.