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Which Diamond Is The Rarest Diamond? World’s Rarest Gems

Which Diamond Is The Rarest Diamond? World’s Rarest Gems

Diamonds are the rarest and most valuable among all gemstones. However, they have varying levels of desirability – and are accessible in varying numbers. As a result, their worth and prices vary significantly from one stone to the next.

Your most effective tool when buying diamonds is information. 

Diamonds are the most popular precious stone on the planet, so most people looking to invest money into them are already aware of the 4Cs – color, cut, carats, and clarity. Even if you’re not, we’ll go over it quickly below.

But what if you wanted to get your hands on something a little different from the standard white diamond? Have you ever wished to own a rare, colored gem and wondered which diamond is the rarest diamond in the world?

Today, we’ll examine the world’s rarest diamond colors, explain how diamonds get their distinct hues, and what makes them so rare and unique.

Let’s get the ball rolling!

A Diamond’s Value

Before we discuss the rarest diamonds in the world, it’s vital to understand what makes them so valuable and how the value of a diamond is determined in the first place. 

Now, the science behind diamonds gets pretty complicated, so we’ll explain in layman’s terms. It doesn’t hurt to understand these precious gemstones a little deeper – especially if you intend to spend a small fortune on one. 

The 4C’s ratings determine the majority of a diamond’s worth – but the most crucial rating is your own. Your diamond might have a symbolic value to you that warrants a higher price – or it might have a narrative attached to it that links you to something or someone.

But, if you’re looking for anything specific, here’s a tip to help you narrow down your options:

Here are the 4Cs in further detail:


The Gemological Institute of America – or GIA – is the global authority on diamond color grading. Colors are rated from D through Z, with Z featuring yellow or brown tones and D used to grade colorless diamonds.

Carat Weight

The weight of the diamond is measured in carats. One carat is equal to 0.2 grams.


On a six-point scale and at 10x magnification, this C represents the number of inclusions (other materials present in a diamond):

  • FL – Flawless
  • IF – Internally Flawless
  • VVS1 and VVS2 – Very, Very Slightly Included
  • VS1 and VS2 – Very Slightly Included
  • SI1 and SI2 – Slightly Included
  • I1, I2, and I3 – Included

Related Read: Are I1 Diamonds Good For Earrings? What Are I1 Diamonds?


The round brilliant cut is, hands down, the most popular form of a diamond. That said, Rose, Asscher, Hearts and Arrows, and Modified Brilliant are all popular cuts – available in Pear, Marquise, Heart, and Triangular shapes.

Diamond’s total value can be influenced by a variety of other factors, such as:

Are Colored Diamonds Natural?

Colored diamonds, like colorless diamonds, are created naturally from carbon deep beneath the Earth’s surface at temperatures more than 1000 degrees Celsius over millions of years. 

Changes in the chemical structure of colored diamonds as they form – which modify how they reflect light and the color our eyes perceive – give them their stunning hues. 

These minor variations are infrequent, occurring in only 0.1 percent of all diamonds. Yet, they may result in stunning colors covering the whole color wheel, including pink, red, purple, yellow, blue, brown – and every shade in between – all created naturally.

Related Read: Are There Real Purple Diamonds?

How Rare Are Colored Diamonds?

Even if they include a trace of yellow, the great majority of diamonds mined across the world are still considered colorless. 

Yellow and brown diamonds make up the bulk of colored diamonds, and the tone and saturation of naturally colored diamonds are frequently lighter. 

Only one genuinely colored diamond will be found in every 10,000 carats mined. 

Finding a naturally occurring colored diamond with medium to dark tones is even more difficult, making every piece extremely rare and valuable.

The Rarest Diamond Color

And now, let’s get down to why you’re here – the million-dollar (quite literally) question: What is the rarest diamond color?

The rarest diamond color in the world is red. But why is it so?

The actual processes that produce red diamonds are yet unknown. They’re considered to be caused by a process known as plastic deformation, which disrupts their molecular structures.

When temperatures are exceedingly high, and pressures are enormous, plastic deformation occurs deep under the Earth’s surface. 

Massive forces knead newly created diamonds like dough until some of the outside atoms “fall out” and glide to another row, where they reattach, generating deformations that refract light into red.

Africa, Brazil, and Australia are the sources of red diamonds.

From 1983 through 2020, the Argyle Mines in rural Kimberley, Northwestern Australia, produced pink, purple, and red diamonds.

Red diamonds are classified as IIa and Fancy. Only approximately 30 genuine red diamonds have been discovered. 

Even if the red is secondary, the price difference between two identically graded red diamonds might be up to 60% per carat. As a result, they can be $300,000 to $400,000 more expensive than the most expensive colored diamonds.

The two most famous red diamonds in the world are:

  • The Moussaieff Red
  • The Hancock Red

The Moussaieff Red, measuring 5.11 carats and rated Fancy Red IF, is the world’s biggest red diamond. It used to be known as the Red Shield Diamond until Shlomo Moussaieff, an Israeli trader from London, purchased it in 2001. It’s one of the top ten most costly diamonds in the world, with a price tag of $1.6 million per carat.

Learn More: Shield Cut Diamond: Proud Member of Step Cut Family

The Hancock Red, formerly known as the Halphen Red, is a .95 carat Brazilian Fancy Purplish-Red diamond valued at $926,315 per carat. It was purchased for $13,500 in 1956 and became renowned in 1987 when auctioned for $880,000. 

It was the first time a gem-quality stone had ever been auctioned.

Other Rare Colors

While red is the number one among rare diamond colors, some other colors and hues are also quite tricky to come upon on the market. Here are a few examples:

Blue Diamonds

The second-rarest color in diamonds is blue.

These diamonds come from India, South Africa, and Australia. Little pipes, known as Kimberlite, push them from deeper layers of Earth to the surface – and the presence of boron and hydrogen is responsible for their hue.

Their grading scale extends from Faint Blue to Fancy Dark Blue, and most feature a secondary color. They’re classified as Type IIb Fancy. A greyish-blue diamond of equal weight can cost 1/7 the price of a Fancy Intense blue diamond.

If you’re a diamond enthusiast, you must have heard of the most famous blue diamond ever – the Hope diamond. It’s worth $200 to $350 million and was mined in India and graded Fancy Dark Grayish-Blue. 

Its most significant remaining portion (45.52 carats) was named after the Hope family of London after it was stolen in 1668 and recut in 1792. The gem was added to the permanent collection of the American Natural History Museum in 1958.

Besides the Hope diamond, two famous blue gemstones are The Blue Moon Diamond and the Wittelsbach Graff Diamond.

The Blue Moon Diamond sold for $25.6 million in the raw, resulting in a 12.03 carat fancy bright IF blue diamond worth $4 million per carat. It was dubbed the “Blue Moon Diamond” because it rated first in hue and clarity. 

The Blue Moon of Josephine was purchased for Hong Kong millionaire Joseph Lau’s seven-year-old daughter for $48.5 million, making it one of the world’s most expensive diamonds.

The Wittelsbach Graff Diamond was initially part of the Austrian and Bavarian crown jewels. It was auctioned in London ten years after being shown in the last Bavarian king’s burial. It was unrecognized when it was displayed in the 1958 Brussels World Exhibition.

Lawrence Graff, a London jeweler, purchased it for $23.4 million in 2008. Despite the uproar, recutting it turned it into a 31.06-carat Fancy Deep Blue IF from a little scratched 35.56-carat Fancy Deep Grayish-Blue VS1.

According to the legend, both diamonds may have come from the same rough stone broken by Louis XIV.

Related Read:

Pink Diamonds

The only known mine in the world with pink diamonds is Australia’s Argyle mine, also known as Argyle diamonds. 

While no less lovely than blue diamonds, pink diamonds are generally more costly owing to their sentimental aspect. Since pink has always been linked with love and passion, this is a popular choice for a diamond engagement ring or a wedding band.

Pink diamonds, like red diamonds, obtain their color from plastic deformation since they lack impurities. 

The Pink Graff is a 14.23-carat Fancy Intense pink diamond. It was auctioned in Hong Kong in 2010 for almost $19 million.

With a weight of 59.60 carats, The Steinmetz Pink, now known as The Pink Star Diamond, is the biggest Vivid Pink diamond ever rated. It was purchased in 2013 for $83 million.

Green Diamonds

Green is a rare fancy diamond, as well. Green gems are among the rarest fancy-colored diamonds because they include nitrogen, hydrogen, or nickel, and irradiation causes them to glow green. They’re mined in India, Africa, and South America.

It’s worth noting that the green layer is frequently a shallow layer that sits on top of the diamond because green diamonds are created by radiation in the soil. Green diamonds with a continuous tint are exceptionally uncommon and fetch millions of dollars at auction.

The Ocean Dream and the Dresden Green Diamond are two of the most popular gems in this color. Internally flawless at 40.70 carats, the rare and beautiful pear-shaped Dresden Green Diamond came from India. The earliest record of it appeared as a London newspaper article dated 1722. It now sits in the Albertinum Museum in Dresden.

The Rarest White Diamonds

White diamonds are more common in mines, but top-ranking diamonds in all 4 Cs are scarce. High-carat-weight, D-grade flawless diamonds are extremely rare – and, hence, quite valuable.

Type IIA white diamonds, often known as Super D or C grade diamonds, contain no nitrogen or compounds and are whiter than conventional white diamonds. Sotheby’s auctioned a Flawless strawberry-sized 102.39-carat white diamond that sold for $15.7 million in the fall of 2020.

Due to the demand and supply law, the rarest diamonds are unquestionably the most valuable. So, buy a rare one whenever you stumble across it. It might just be the best investment option you’ve ever made!

How To Get The Rarest Diamonds?

The truth is, you most likely won’t be able to get your hands on the rarest of them all. 

  1. First off, these gems have astronomically high prices; we’re talking tens of millions of dollars here.
  2. Secondly, since there isn’t an infinite number of these unique stones, you can’t simply walk into a jewelry store and buy one. 

They’re either sold at auctions or kept in museums – at least the ones we’ve mentioned today. Generally speaking, the auctions are the ideal place to look for a rare diamond selection – if you’re able to participate in one, that is. 

However, this requires special knowledge and significant financial expenditure. 

For example, have you heard of Sotheby’s, the great event that showcases modern art, wine, and jewels? Well, it’s the most famous example of such an auction in the industry.

Rarest Diamond In The World: Conclusion

The rarest diamond color category winner is hands down, red. Red diamonds are – and will remain – at the throne for their beauty, fineness, and, most of all, their scarcity. 

It would be incredible if these breath-taking precious stones were available to us in larger quantities, but wouldn’t that defeat the purpose and the whole point of owning a beautiful, extremely rare red diamond?