How is Diamond Formed in Nature?

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Diamonds are undoubtedly the most enigmatic specimens of the gemstone world, mainly because of its beauty and rarity. The most historical finds and jewelry settings for diamond fetch millions of dollars each, and like gold, the value of diamonds will only increase over time because of its scarcity.

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What is a Diamond?

A diamond is a gemstone that is made primarily of carbon. Because of this, many people think that diamonds are formed from coal.

While this is technically possible, much of the world’s diamond supply does not come from coal. The reason for this is that diamonds outdate many of the plants and animals that have lived on this Earth for millions of years.

They predate living materials that eventually become coal, so it is no longer a matter of asking which came first because diamonds (being comprised of carbon) came first.

How is Diamond Made?

The majority of the diamonds mined either for industrial purposes or jewelry is from chunks or portions of the Earth’s mantle that was blown to the surface.

We don’t always see volcanic activity. Much of the volcanic activity that we see involve lava and magma, and the same things happen deep under the Earth – about one hundred miles down from the planet’s surface.

Open-ground or deep pit mining of diamonds is constructed when more substantial quantities of the mineral are found. This isn’t always done because deep pit mining is expensive, and mining operations have to be profitable in order to succeed.

Diamonds are formed about ninety to one hundred miles beneath the planet’s surface, at temperatures that often exceed 2000˚ F or 1050˚C. Does this mean that diamonds can occur anywhere in the world?

Not necessarily. Diamonds require a stable environment for pressure and temperature to combine, so diamond crystals emerge. Experts believe that diamonds can only form in areas where the continental plates are relatively stable.

These spots are called “diamond stability regions,” and whenever there is enough pressure from volcanic activity, these areas yield diamonds for all kinds of applications.

The reason why coal is rarely involved in the formation of diamonds is because of the depth at which they are formed. Coal is usually found three kilometers from the surface, a far cry from the ninety to one hundred miles where natural geological processes usually deposit diamonds.

What about diamonds grown in laboratories?

Lab-grown diamonds have been produced since the fifties, and these diamonds are chemically identical to naturally formed diamonds. Trained gemologists will be able to spot the differences between natural diamonds and lab-grown diamonds.

However, this does not mean that lab-grown diamonds are any less valuable to people. Many people choose lab-grown diamonds because they are less expensive and can buy diamond jewelry without spending a large chunk of their budget.

Now, there are physical differences between natural diamonds and synthetic ones. The most obvious difference is the blocky form factor of synthetic diamonds.

High-temperature formation of diamonds deep beneath the Earth, in the mantle form octahedral facets. Now, synthetic diamonds that have been faceted to look like natural diamonds can still be differentiated from the natural ones, again, by trained gemologists using specialist knowledge and tools that can be used to compare gems.

The Value of Diamonds

Let’s talk about some of the particular types of diamonds that are mined worldwide. Generally speaking, colored diamonds are considered more valuable because they are rarer than white diamonds. In terms of scarcity, there is an entire spectrum of diamonds that are extremely rare anywhere in the global market.

This spectrum includes yellow diamonds, orange diamonds, blue diamonds, green diamonds, and the like. Jet black diamonds have also been found, as well as gray ones. Chromatic changes in diamonds are rare, and jewelers around the world highly value colored ones.

While rare, gray, and black diamonds are less expensive than yellow diamonds, which are highly prized in the market. Fancy yellow diamonds can fetch up to $10,000 per carat. At the very least, a carat will bring at least $5,000 for fancy yellow diamonds. The rarest of them all are red, violet, and orange diamonds, which are in even lower supply. These diamonds are so rare that a single carat of red diamonds, for example, can easily be valued at a million dollars. This is a massive throwback to the $5,000 or $10,000 value for less rare variants, like yellow diamonds or blue diamonds.

Where are highly valued diamonds sourced?

There are only a few locales where colored diamonds are regularly unearthed and processed for the global market. A prime region for rare diamonds is the Golconda Sultanate, which is found in India. The diamond mines here (which now includes two modern Indian states) have been yielding rare diamonds since the 1400s. Some of the notable diamonds unearthed in India include the 43.8-carat blue Nassak diamond, the 60-carat Noor-ul-Ain pink diamond, and the large 67-carat blue Hope diamond.

In Australia, the Argyle Mine has been yielding pink diamonds, red diamonds, and violet diamonds since 1985. Again, these ultra-rare diamonds fetch at least a million per carat because of their extreme rarity. The Argyle Mine is notable for consistently producing chocolate diamonds, which only made the jewelry market in the mid-1980s.

The ALROSA mines in Russia are another excellent example of a rare diamond locale. The ALROSA mines are the number one source of fancy, colored diamonds in the world. Russian diamond deposits lie north of the Arctic Circle, and the sheer number of colors of diamonds unearthed here is simply spectacular. Russian diamonds come not only in pinks, reds, and blues but also lilac. Alluvial deposits along the Ebelyakh River are the primary source of these unique diamonds.

Finally, if you are interested in the enigmatic green diamond, you will have to find a jeweler who has access to the Golconda Mines in India. This locale is the center of green diamond production in the world.