Degree or depth of colour in terms of lightness or darkness. The tone of a coloured diamond can range from very pale to very dark; it is the degree to which the colour of a diamond approaches white on the pale end, and black on the dark end.
The Diamond Certification Laboratory of Australia (DCLA)
Diamond Valuation Certification and advice from the Diamond authority in Australia
Degree or depth of colour in terms of lightness or darkness. The tone of a coloured diamond can range from very pale to very dark; it is the degree to which the colour of a diamond approaches white on the pale end, and black on the dark end.