One range, distinct grades
D, E and F are separate colour grades within the colourless range. Compare the laboratory report rather than accepting a broad range as the exact grade of an individual stone. A small grade difference may be difficult to see in everyday viewing.
Context changes perception
Lighting, nearby colours, metal and cut influence appearance. Larger stones and open step-cut patterns can make body colour easier to assess. A yellow or rose-gold setting creates a different visual context from a white-metal setting.
Compare under the same conditions
Ask for comparable views against a neutral background and in more than one lighting environment. Avoid judging colour from differently exposed or processed photographs. A screen cannot reproduce the full experience of the stone.
Spend for the result you want
A price difference between grades is not necessarily a visible difference on the hand. Balance colour with cut, clarity and dimensions. Confirm the exact grade and final price in the individual quotation.
Sources and further reading
This English edition draws on the source material referenced below.