Fancy Coloured Diamond Guide
All about the different types of rare, fancy coloured diamonds.
Natural fancy purple diamonds with pure colour are extraordinarily rare. These precious stones are seldom found in sizes larger than 5 carats. It is much more common for purple diamonds to weigh in on the smaller end, normally no more than 2 carats, but generally much less.
The source of the natural colour of purple diamonds is an intriguing mystery. While some violet diamonds contain boron, which causes the blue colour in diamonds, others have traces of hydrogen instead.
Still, others have structural anomalies in their crystals, similar to pink diamonds. But because purple diamonds are so rare, scientists can’t say for sure what causes this surprising colour.
Light purple diamonds can include lovely lavender, lilac, orchid, and mauve colours that create beautiful purple diamond engagement rings. Only a few pure purple diamonds are found in the world each year. Purple diamonds have been found in South Africa, and two mines in Russia have also produced a small number of diamonds with purple as their dominant hue.
The Argyle Mine in Australia is one of the only sources of violet diamonds. Most of the world’s diamonds with a pure violet hue have been mined from Argyle.
Only 12 carats of violet diamonds have been found in 32 years of the “Argyle Tender”, which is the annual sale of the mine’s best quality fancy coloured diamonds.
Fancy red diamonds are considered the holy grail of all fancy colour diamonds. It is an undisputed fact that natural pure red diamonds without any secondary colours are the rarest of all.
These particular diamonds are so scarce that the world-renowned Gemological Institute of America (GIA) only releases about one graded report featuring “Fancy Red” every 30 years or so.
Natural red diamonds are so hard to come by that up to a mere 30 are known to exist. Not surprisingly, due to the total scarcity of fancy red diamonds, this particular diamond colour commands the highest price per carat and will only continue an upward trend.
Fancy colour diamonds are found in twelve different colours, but with over 230 colour combinations and in various locations around the globe.
The majority of red diamonds, in particular, originate from Australia, in the Argyle diamond mine which is famous for its production of some of the world’s finest pink, violet, blue, and brown diamonds. However, a large percentage of these diamonds have also been found in Brazil, Russia, and India.
The origins of the highly coveted colour in red diamonds remain undetermined although the prevalent theory is that, much like in pink diamonds, structural defects arise from small movements occurring in the atoms, a process referred to as ‘plastic deformation,’ giving these exceedingly rare diamonds their distinctive colour. The structural defects materialize as a series of tightly positioned grain lines that exude red colour. Colour intensity in red diamonds is directly correlated with the amount of graining present: more graining means a more intense red diamond.
Pink diamonds have been sourced in very limited supply from mines around the world. In the 17th and 18th centuries, rich discoveries of pinks were made in India and in Brazil.
Since the late 1980s, over 90% of the world’s fancy pink diamond supply has come from the Argyle mine in Australia.
It is very common for pink diamonds to display fluorescence. In fact, finding a real pink diamond without this quality is quite rare.
Hence its presence usually does not have a negative impact on the price (even in the case of strong blue fluorescence). According to the GIA, over 80% of all pink diamonds exhibit some degree of fluorescence.
In the final analysis, the enhancement to a stone’s aesthetics that fluorescence offers is entirely subjective. Fancy pink diamonds tend to be included, yet because of their rarity, clarity plays a much smaller part in their valuation, in comparison to their colour.
A “brownish pink” diamond refers to a pink diamond with a slight touch of brown hue in it, while a “brown pink” diamond denotes a more obvious brown colour. A brown pink diamond is cheaper than a brownish pink diamond. A brownish pink diamond has about 25% brown, while a brown pink diamond has about 25-50% brown in it.
Within the brownish pink diamond range, there exists a wide spectrum of how influential the brown colour really is. This is why you can often see two diamonds with the same brownish pink colour description in the certificate that is very different in terms of their price.
Pure coloured diamonds are usually much more expensive, while brown diamonds are cheaper, so adding the brown colour as the secondary tone reduces the price of the diamond quite dramatically.
For those who wish their diamond to be more obviously coloured, a diamond with a naturally darker brown will do the trick.
In the end, it is all about the appearance of the diamond and what you personally prefer.
Brown diamonds are among the most common, along with yellow diamonds, and are the most affordable of all coloured diamonds, besides black diamonds. Brown diamonds are also known as Cognac, Champagne, or Chocolate diamonds. Brown diamonds are found in many shades ranging from subtle brown hues to vibrant chocolate-like colours.
The C1 to C7 colour scale is used to grade champagne diamonds. C1-C2 is the lightest brown colour, and C5-C6 is the darkest brown of the champagne diamonds. C7 is used for the darkest, richest brown of the cognac diamonds. The more intense and vivid the colour in the brown diamond, the rarer, and more valuable it becomes.
Brown diamonds provide a harmonious contrast in jewellery pieces, especially if placed next to white diamonds.
Fancy brown diamonds are not part of the D-Z colourless diamond scale, as the two scales grade the colouring in the diamond very differently. The well known D-Z scale grades colourless diamonds, going from completely colourless diamonds graded as D to colourless diamonds with warm hues, graded as lower letters in the alphabet.
The fancy brown diamond scale grades colourful diamonds that have a higher and lower saturation of the colour brown.