Science tells us otherwise, and it is nitrogen, the rather less romantic element, that billions of years ago differentiated a colourless diamond from its daffodil-bright sibling.

The yellow is the only coloured diamond whose grading begins on the lower end of the GIA D-Z grading scale and continues into the ‘Fancy’ hues, giving yellows the widest and most fascinating range of variants.

The most prized are the four Fancy grades, from Fancy Light to top-of-the-range Fancy Vivid, with its perfect equilibrium of colour and saturation.

Until the discovery of diamonds in South Africa in the second half of the 19th century, few yellow diamonds had been found. Those from existing sources in India and Brazil were considered natural wonders worthy of curiosity cabinets and royal collections.

But today, yellow diamonds are one of the most sought-after gems, and that is in no small part thanks to four decades of work by Laurence Graff, who was one of the first to shine the spotlight on Fancy yellow diamonds at a time when only white would do.

Laurence Graff recalls the moment in New York, in the 1970s, when a diamond cutter showed him a 31 carat yellow diamond. He was taken aback by how the radiant cut maximised its colour. Following his heart, he bought the stone, and from that moment on it could be said he had contracted an enduring case of yellow fever.

It wasn’t long before he acquired and recut his first headline-grabbing yellow, the 47.39 carat Star of Bombay, followed since by almost two dozen more outstanding yellow diamonds that are among the finest of their kind in the world.

The Fancy Vivid grading for a yellow diamond is light to medium in tone. It should not be too dark and have a very high saturation or strength of colour.

In this category, the deep yellow colour is shown to its best effect, making it the most desirable colour grade. Although, beauty is in the eye of the beholder, and other grades and colours can be every bit as pleasing.

Beyond its attractiveness, a yellow diamond is a window into the workings of our planet. While a jeweller seeks out perfection, as a scientist I am interested in the imperfections.

Each trapped particle can tell us what minerals are forming deep within the planet that help to understand our earth, and even if there might be diamonds on other planets.

And, remember, as we live on a dynamic planet, beneath our very feet diamonds are still being formed that may see the light of day millions of years from now.

At the wheel, all we have is our eyes and some basic tools, and we really have to look for the colour. Each stone is different and a research project in its own right.

It takes about six weeks to polish a one carat yellow diamond within the overall three-month process. But a big diamond can take a year or more to polish.

We progress very slowly and gently, as yellow diamonds are more stressed than colourless diamonds due to their crystallisation process, which means they react differently at the wheel.

It is also important to take into consideration the provenance of a coloured rough diamond as geological differences affect the hue and intensity in different ways, and how the diamond reacts to the polishing process.

An experienced cutter can look at a rough diamond and evaluate what the final colour will be. This is down to experience, as often we are looking at diamonds at auction and are not able to make a window into the stone. But, even so, we can fairly accurately estimate the intensity and purity of colour.

Once a yellow diamond is in our possession, we aim to take the colour up a level, from say Fancy Intense to Fancy Vivid, but it is always a gamble and not an exact science. Within each colour grade there are many subtleties of shades and intensity, so it is about finding the most beautiful cut for each stone.

This is the old art of the polisher that only experience can teach.

The range of yellow diamonds with which I work is exceptional in terms of colour, quality, cut and quantity. Few jewellers have the luxury of such a wide range of yellows at their fingertips, from the traditional colour gradings — Light to Vivid — but also exceptional examples of other colours such as Deep Orange Yellow and Brownish Yellow.

Because we have many valuable diamonds and also some of the rarest in the world, the design of a yellow diamond jewel is often based around the stone. I don’t dream up an idea and then look for the diamonds – I start with the stones. And in our atelier, diamonds, the epitome of femininity, are always referred to as ‘she’.

It is vital to know the stones intimately so I hold them in my hands every day. Our London studio faces north, which offers the perfect light for looking at diamonds. I spend a lot of time studying each one, even before my initial gouache drawings take shape.

With yellow diamonds in particular, I love making bracelets or watches that feature more than one stone. You don’t see this very often as other designers simply don’t have the yellow diamonds to choose from to create these magnificent combinations.

When you see a bracelet or earrings made from dozens of yellow diamonds, the colours are so vibrant that they look almost unreal. And there is a skill to combining them so that the Vivid diamonds, the brightest of them all, don’t steal the show.