The yellow seen in diamonds is caused by the trace element Nitrogen. Other trace elements create a rainbow of colours in diamonds. These coloured diamonds are termed "Fancy Colour" diamonds. They have a separate grading system. This system begins with any diamond that has a stronger colour than a Z in the standard grading chart.
Colours include pink, yellow, red, and blue. Most are extremely rare and come at a premium to traditional colourless diamonds with the exception of black, brown, or "champagne" coloured diamonds.
Brereton Jewellers have a selection of coloured diamonds. Please contact us via firstname.lastname@example.org for a list of our current range of coloured diamonds.