April’s birthstone is diamond and many people are surprised to know that diamonds can come in virtually all colours of the rainbow. This post will be the first of a series entitled “Captivated by Colour” where we explore each of the fancy diamond colours in turn, together with what gives the diamonds their colours, where they come from, what the prices of coloured diamonds are and, of course, some famous coloured diamonds.

Whilst most coloured diamonds are exceptionally expensive (especially in South Africa with our weak currency), yellow diamonds are perhaps the most affordable of the fancy colours (except for black diamonds, of course), so we’ll kick off our series with yellow.

What gives yellow diamonds their colour?

Diamonds are the purest gemstone we know of, made almost exclusively of carbon. When a diamond grows in the mantle of the earth, in what can only be described as a “chemical soup mix”, it’s only natural that other elements may be incorporated into the diamond as it grows. When the element nitrogen is incorporated during diamond growth, the diamond will turn yellow. The higher the proportion of nitrogen in the diamond, the more yellow it will be. It’s important to note that yellow diamonds are not any “weaker” or less hard because they have a small percentage of nitrogen in their composition; we’re looking at tiny parts per million (ppm) proportions of nitrogen.

Where do yellow diamonds come from?

South Africa’s diamond rush was triggered in 1867 when Erasmus Jacob’s discovered our very first diamond. The “shiny pebble” he found in a river bed turned out to be a 21.25ct yellowish-brown diamond, which was cut into a 10.73ct gemstone. Since then, South Africa has been a prolific producer of some of the most vivid yellow diamonds available today. Other countries that produce yellow diamonds include Australia, Angola, the DRC and Canada.

South Africa's first yellow diamond

The Eureka Diamond, South Africa’s very first diamond. Image via Wikipedia Creative Commons. 

How are yellow diamonds graded?

Fancy coloured diamonds (like yellow diamonds) are graded in a slightly different manner to the traditional 4C’s that you associate with white diamonds. On the white diamond colour scale, diamonds closer to the bottom half of the alphabet (from “L” downwards) have a noticeable yellow tint to them. However, it’s important to note that these are considered tinted white diamonds, rather than fancy yellow diamonds. Sometimes, these pale yellow diamonds on the D-Z scale can be called “Cape yellows” or “Champagne” diamonds.

When it comes to the rich, vivid yellow colours that you’re probably thinking of, the GIA has a completely different colour scale, which takes into account the hue, tone and saturation of the diamond. The richest colour yellow diamonds will be classified as “Fancy vivid” colours, whereas a more pale yellow will have a “Fancy” or “Fancy Light” grading.

GIA colour diamond scale

The GIA Coloured Diamond Scale. Image via GIA.

 

 

Princess cut yellow diamond

A fancy light yellow rectangular princess cut diamond.

 

Yellow diamonds south africa

A fancy vivid yellow (top colour grade) yellow diamond. Note the difference in colour compared to the fancy light princess cut diamond above.

Often, coloured diamonds are cut into fancy shapes (any shape other than round) to maximise the distribution of colour in the diamond. Additionally, the yield (ratio of rough diamond size to cut diamond size) is better when diamonds are cut into fancy shapes such as oval and radiant cuts.

The clarity of yellow diamonds is graded the same way as traditional white diamonds, using a scale from Internally Flawless to Included.

How much is a yellow diamond in South Africa?

The prices of yellow diamonds in South Africa vary according to the intensity of the yellow colour, in addition to the size and clarity of the diamonds. A pale, faint yellow diamond will cost much less than fancy intense yellow, which will in turn cost less than a fancy vivid yellow.

A 0.50ct round fancy yellow diamond can cost in the region of $800 (+/- R14,600) but we’ve also got a 0.97ct rectangular princess cut natural fancy light yellow diamond for $1540 (+/- R28,000). We’ve also sold a fancy vivid yellow (top yellow saturation) oval cut diamond for $10,300 (+/- R187,460). To see what exactly is in stock and what current prices are, reach out and contact us.

Round fancy yellow diamond

A 3ct round fancy yellow diamond in an 18ct yellow gold ring.

What are some famous yellow diamonds?

 The Tiffany Yellow Diamond

Discovered in Kimberley, South Africa in 1878, the original rough stone weighed a whopping 287.42ct. Cut and polished into a 128.54ct cushion cut, it is owned by Tiffany &Co. and has only been worn by 3 women in its entire history. The most recent woman to have the honour of wearing it was Lady Gaga, who wore it to the 2019 Academy Awards.

The Tiffany Yellow Diamond was found in South Africa

The Tiffany Yellow Diamond. Image via Wikipedia Creative Commons.

The Cora Sun-drop Diamond

Discovered in South Africa, in 2010, this pear-cut diamond weighs 110.30cts and was sold for $10.9 million in 2011. Auctioned by Sotheby’s, the GIA has graded the diamond as a Fancy Vivid Yellow with VVS1 clarity. It is the largest known yellow pear-cut diamond in the world.

Pear cut yellow diamond mined in South Africa

The Cora Sun Drop diamond. Image by Sotheby’s.

We hope that you know much more now about yellow diamonds and you can appreciate their beauty even more than you did before. If you are looking for yellow diamonds in Johannesburg or South Africa, and don’t want to pay retail jewellery store prices, reach out and contact us for a private diamond consultation. We’d be delighted to assist you with the perfect yellow diamond.