If I asked you picture a diamond in your mind, what do you think of? Most people think of a transparent, colorless, sparkling gemstone set in an engagement ring. But what if I asked you what your favorite color was? Then what if I told you it was a legitimate possibility to find a diamond that color?
Most people respond with a mix of pleasant surprise and guarded skepticism. Some people automatically assume it’s out of their budget. Others are cynical of the origins and assume they are all “fakes.” And then there are those who get excited about even having the option and want to explore it when they realize it might not be as far-fetched or “fake” as they may have initially suspected.
In short, diamonds of every color have been found naturally. They are called “fancy-color” diamonds in the trade. There are 27 recognized hues (red through purple) and over 300 variants of those hues (deep brownish pink, slightly grayish blue, etc.). It’s true that fancy-color diamonds can be expensive, sometimes exclusively so, but you might be pleasantly surprised by the availability of some colors.
With all other grading criteria equal, truly colorless diamonds (D-color) are still rarer and often more expensive per carat than several grades of fancy-color diamonds. Many people are surprised by that. If there is a bargain to be had in the world of fancy-colored diamonds, yellows and browns are where it’s at. Prices fluctuate yearly with fashion trends, but as of this writing, some of the stronger intensity levels are less expensive per carat than even G- or H-color stones on the traditional color scale. True blacks, chocolate browns, cognac oranges, and olive greens (highly brown modified) are often in this range. Even some fairly strong-colored pure yellows are available for the same price per carat, if not less, than a D-color diamond of comparable weight, clarity, and cutting.
However, most of the other natural colors can be pretty pricey. Natural reds, purples, and greens can be astronomically expensive due to their rarity. Natural red diamonds with no modifying hue are often considered among the rarest gems in the world, and it’s not uncommon to see prices start at $500,000 per carat. Purples and greens are not far behind that, if not right on par with it.
Greenish-blues, pinks, pure blues, and oranges are next in line, although certain modifying tones like brown and gray can switch those orders around. It’s important to remember that purity and intensity of color drive the price of a fancy-color diamond more than anything except carat weight. If some of the rarest colors are especially deep in saturation, color can even supersede carat weight.
Pinks are usually modified by at least a little brown, while blues are almost always modified by gray. Blues often look “steely” because of this. Even the Hope Diamond, probably the most famous diamond in the world, is blue modified by gray according to its official color report by GIA.
The other side of fancy-color diamonds is treated stones. Most of the same colors that have been discovered naturally have also been achieved through after-mining treatments like irradiation, annealing, high-pressure/high-temperature (HPHT), or some combination of the three. Unfortunately, some are even coated, which is not a permanent or stable treatment. Like any gemstone, treated diamonds are exceptionally less than their certifiably natural counterparts, but some of the stable treatments produce very attractive colors that would otherwise stay far beyond the means of many people.
As a rule, I stay away from coated stones, which usually appear pink. That treatment is unstable, and I don’t like using things that can be damaged so easily, either by my working on it, or my client wearing it. But irradiation, annealing, and HPHT treatments are all pretty stable. I’ll find them and sell them if a client asks, but they’re not my first choice.
If ethically represented for what they are, treated fancy-color diamonds are always an interesting avenue to explore for someone with a modest budget who is looking for something unique. That’s the point of their development, after all – to offer an intensely colored diamond at a fraction of the cost of its natural alternative.