While many of the basics of how to buy a diamond apply to all diamond types, they vary a bit among the different colours. Such is the case with fancy white diamonds which are one of the most alluring and remarkable in the family of fancy colour stones. Get ready to fall in love.
What Are Fancy White Diamonds?
Fancy white diamonds, also known as opalescent diamonds, belong to the fancy colour diamond family. Although the term “white” is often applied to colourless diamonds that fall within the D-to-Z colour scale, these diamonds are not white at all. The hues of colourless diamonds can range from pure colourless to light yellow, light brown or light grey, while natural white diamonds fall outside the traditional colour scale and have a distinct opaque white colour.
Opalescent diamonds are the natural phenomenon of colour diamonds because white does not appear on the colour spectrum; white is the sum of all colours. They owe their remarkable colour to the presence of billions of sub-microscopic inclusions that scatter light passing through a diamond. This results in a “milky” translucent face-up appearance. It is worth mentioning that the nature of these sub-microscopic inclusions is unknown, although according to some sources, they are thought to be nitrogen traces within the pure carbon structure.
Fancy white diamonds are very rare, and there is no specific mine that these stones come from. The ones that were submitted to GIA came from the Panna mine in India.
Evaluating Fancy White Diamonds
Since natural white diamonds belong to the family of colour stones, they receive a Coloured Diamond Grading (CDG) Report. However, grading of fancy white diamonds is challenging as their limited transparency makes some observations very difficult. That is the reason why most fancy white diamonds receive a Coloured Diamond Identification and Origin Report instead. Statistically, only 30% of all fancy white diamonds submitted for grading received CDG reports in the last decade.
The GIA Coloured Diamond Identification and Origin Report (CDIOR) describes the colour grade of a diamond and the colour origin (natural or treated). This report is not issued for diamond simulants or stones that have undergone non-permanent treatments, such as fracture filling or coating.
Since white is a neutral colour, opalescent diamonds are not measured by the level of saturation. In most cases, they receive a “Fancy White” colour grade; however, these diamonds can be modified by grey, pink, blue, green, and brown hues. Unlike white diamonds, other fancy colour stones are graded based on the intensity of their colour. As a general rule, the more saturated the colour of a fancy diamond, the more valuable it is.
As for the clarity, white diamonds are extremely clouded, and they usually fall within the Included range (I1, I2, I3). Their appearance can be transparent, transparent to translucent, translucent and translucent to opaque. The more opaque and distinct the white colour, the more rare and valuable the stone is.