What Is Diamond - Gemstone Facts and Information

| 15 min read

Diamond is (and has been for centuries) the most famous of all precious stones. It has been used in jewellery for many generations, and are coveted perhaps more than any other gem. The story of Diamond begins over 500 million years ago, deep within Earth’s Mantle, where they were formed under immense pressure.


Said to be “a girl’s best friend”, the name 'Diamond' derives from the ancient Greek word ‘adamas’ meaning 'invincible', which it gained because of its sheer strength. Diamond is the toughest gemstone (and one of the toughest materials) known to man.

Diamond infographic

As far back as the first century AD, when Pliny the Elder (AD 23 to 79) wrote that "Diamond is the most valuable, not only of precious stones, but of all things in this world", the stone has captivated all who encounter its undeniable charm. Diamonds form very deep in the Earth's mantle, much deeper than most gemstones at around 100 miles under the surface. It's Mother Nature herself that brings these deep-level treasures to the surface, through deep source volcanic eruptions that rapidly carry parts of the mantle upwards.

In certain areas around the world, these eruptions will pass through an area where Diamonds have formed and will pick up and carry some of them higher, until they're on or very near the surface. The remnants of these eruptions leave pipes made of kimberlite (a type of igneous rock), which plunge back down deep into the earth.

Essentially, finding a kimberlite pipe is page one of how to find Diamonds; when you see a kimberlite pipe, these precious stones aren't often far behind.

High end Diamond jewellery

Unlike biblical gemstones such as Amethyst, Topaz, Ruby and Sapphire, very little was documented about Diamonds until the 14th century. However, the earliest Diamonds are thought to have originated in the streams and rivers of India, possibly as early as the fourth century BC. This limited alluvial supply meant that only the very wealthiest could afford to invest in this sparkling new discovery.

The discovery of Diamonds remained a local secret for a long time, though eventually the word began to spread and by the 1400s the upper-classes of Western Europe were adorning themselves with Diamond jewellery and accessories.

White Diamonds

It was not until this period that the first rudimentary facets were being applied to the gem. As many rough Diamonds are octahedral in shape (imagine two pyramids attached to each other at the base), by simply adding a table facet, many early cuts closely resembled the shape of today’s 'brilliant cut' Diamonds. By 1521, King Henry VIII had a crown adorned with Diamonds, among other precious stones.

India's monopoly on Diamonds broke in the 1700s when Brazilian Gold miners started to find Diamonds in their pans whilst sifting in streams. India's supply was beginning to dwindle too, and Brazil was subsequently able to go for over 100 years as the world's main Diamond source. At this point, the popularity of Diamonds was still hindered by their extreme rarity and subsequent high cost.

Blue Diamond Rings

Then, in 1866, everything began to change with the discovery of Diamonds in Kimberley, South Africa. (There's no coincidence here; Kimberley is so important to the history of Diamond that the kimberlite rocks mentioned earlier were named after the town).

In a very short period of time, gems from this region would account for over 90% of those on sale globally. The new supply put Diamonds within the reach of many more people, though prices remained relatively high because the supply chain was very tightly managed.

The company at the centre of this huge growth was De Beers, established in 1888. De Beers Diamonds were synonymous with the entire industry for much of the 20th century; this new kid on the gem block went from being almost entirely unknown to unquestionably the global leader of the Diamond supply within half a century.

This was helped by their huge marketing campaigns, one of which, in 1948, popularised the phrase, "A Diamond is Forever", which was later voted the top marketing slogan of the 20th century.

De Beers Diamond rings

For those interested in studying advertising and marketing, the rise of the Diamond to the status of the world’s most popular gemstone is a real textbook campaign. It is even credited with inventing the modern engagement ring and, before this campaign, the Diamond was much less frequently chosen as the stone for a bride-to-be.

In 1919, Marcel Tolcowsky described his brilliant cut for the first time, which standardised the dimensions of the 'perfect Diamond cut'. Different cuts of Diamonds do exist, but this one remains by far the most popular and common, with just a few small modifications since the original specs were published. Through much of the 20th century, Diamond sourcing remained relatively unchanged, with much of the supply coming from South Africa, with the then Soviet Union also being a source.

Diamond Ring

In 1982 there was a significant new Diamond find in Botswana, with Australia joining the list in 1985 and Canada in 2000 with their own major finds. There are also a handful of other countries that contribute to the supply of Diamonds. Mining techniques and yields improved significantly over the 20th century, with around three million carats being mined globally in the 1920s, rising to over 100 million carats a year in the 1990s.

The trend in recent times has been slowly swaying back towards Mother Nature's more colourful gemstones, but there is a still a huge global appetite for this fiery treasure.


Pink Diamond Jewellery

Diamond is the birthstone of April, and is the given gift of the 10th, 60th and 75th wedding anniversaries. Of course, many people also hope to receive a Diamond engagement ring. The gem features a cubic crystal system, and as well as their most well-known appearance of beautiful bright white, natural Diamonds have been found in yellow, green, blue, orange, red, pink, purple, brown, grey and black.

There are also methods to enhance White Diamonds with colour, which are much more affordable and allow a greater number of people to enjoy a rainbow of hues in this fiery gem.

At Gemporia, we always disclose if your Diamond (or any other gem) has been treated in any way.

Diamond Engagement Ring

Have you ever asked yourself, "How are Diamonds formed?" or "What are Diamonds made of?" Well, Diamond is a gemstone made of pure, native crystallised carbon, with the oldest Diamonds believed to be almost 3.5 billion years old.

Many Diamonds began their journey 500 million years ago, and even the youngest are believed to have formed over 100 million years ago. They crystallise when carbon is put under immense pressure of around 725,000 pounds per square inch, and at a temperature ranging from 900 to 1,300 degrees Celsius.

Champagne Diamond Ring

As we've touched on already, for these conditions to occur naturally it is thought that Diamonds were created some 90 to 120 miles beneath the Earth’s crust. This means that they actually form while still inside the mantle, an area deep within the earth that is made up of hot flowing magma. The only other valuable gem on the planet to crystallise under these hostile conditions is Peridot.

In the gem world, more people are employed in mining and cutting Diamonds than for any other gemstone. Diamond grading is very important too, and it's essential to maintain a robust grading system to protect fair Diamond pricing.

A lot of people think that the clarity of Diamonds is the only deciding factor in their value, but there's a little more to it than that. In fact, the quality of the gem’s colour, clarity and cut are more tightly measured for a Diamond than for any other gemstone. Importantly, the value of similar Carat weights of Diamonds can vary dramatically based on their Colour, Clarity and Cut.

Diamond Grading

These 4 Cs make up the grading system against which Diamonds are measured, and although there are various standards used across the globe, that of the Gemological Institution of America (GIA) is the most widely used. A Gemporia Diamond is strictly graded against the 4 Cs, and our Diamond graders assess the potential of each one before the design team create jewellery to showcase their beauty.

Our Diamond sorters also examine the stones by hand for any visible inclusions or colour variations against the GIA's recognised grading scales.

For more information on how we grade our precious stones, read our blog on the 4 C's of Diamond grading.

Monochrome Diamonds

Its very high refractive index (2.417) is what gives the Diamond its famous sparkle; its strong lustre is described as an 'adamantine' (appropriately enough meaning 'Diamond-like') lustre. One of the main differences between Diamond and many other gemstones is that a lack of colour is highly prized. The closer to colourless a Diamond becomes, the better dispersion (the splitting of light into its constituent colours) it will display.

It is often taken for granted that the larger the carat weight of a good quality gem, the larger the price - but why is this the case? In simplistic terms, larger gems are rarer than smaller gems and in the case of Diamonds, only one in a million faceted Diamonds are said to weigh over one carat.

Diamond jewellery

Diamond is such a hard gemstone that it can only be cut by other Diamonds, and although they are extremely hard they are also quite brittle, making them one of the more difficult gems for lapidarists to shape.

A question that's often asked about Diamonds is whether they're formed when coal is compressed. It's a very popular myth and they are both indeed different forms of carbon, but coal tends to sit just a couple of miles under the surface of the earth and Diamonds form much much lower and in very different, much harsher conditions.

It's also commonly asked whether Diamonds are rare; well, any gem quality mineral is rare by definition, but Diamond is actually one of the most common among gemstones.

Yellow Diamonds

You may have always thought of Diamonds as a colourless gem, but a rainbow of beautiful colours is possible. In fact, laboratories use a list of 27 different colour variations to describe a Diamond’s colour. These colours are all caused by different things – from different impurities in the gem to distortion in the gem’s crystal lattice structure.

Black Diamonds, on the other hand, are believed to have come from outer space! Coloured Diamonds are some of the most highly valued gemstones on Earth, and sparkle with a rainbow of vivid beauty. Some of the most treasured Diamonds on the planet are coloured, including the most famous gem of all - the Hope Diamond, pictured below.

Blue Hope Diamond

Normally, if an auction company break their in-house record for the sale of a Diamond, it will be for a coloured stone. Popularity has grown for these Diamonds in recent years, thanks in part to Australia’s Argyle mine, which brought Champagne and Cognac Diamonds to the market.

Demand for coloured Diamonds is increasing, and Gemporia brings the full spectrum of these Diamonds at affordable price points.


Gemstones are as old as time, and in the years since their first discovery they've picked up a lot more than adoring collectors and fascinated mineralogists. Many have gained stories regarding their legend, lore and healing properties, and whilst there's no evidence to suggest that any of these properties are real, it's still interesting to explore the esoteric side of Mother Nature's miracles.

Solitaire Diamond

It's worth asking ourselves: "If you truly believe in something, does that mean it's true"? Scientifically, the answer is no, but what about on a more personal, spiritual level? If you really truly believe that an item in your house is having an effect on you, are you more likely to feel that effect? It's really not for us to say, but it's a very interesting concept that deserves further research.

Once again, though, we must point out that no studies have ever found any therapeutic effects or properties in gemstones, and the following is for your information only.

Those who consider Diamond a spiritual stone see it as a representation of perfection, and its sheer strength has earned it associations with invincibility, courage and strength.

Diamond rings

Diamond is thought to encourage open-mindedness and strengthen ones imagination and creativity; perhaps its place as the gemstone of choice for engagement rings was rooted in the fact that it has been associated with innocence, faithfulness and, of course, love. Diamond is also associated with the zodiac sign Aries.


  • Colour Colourless, yellow, green, blue, orange, red, pink, purple, brown, grey and black
  • Mohs Scale Hardness 10
  • Specific Gravity 3.5
  • Refractive Index 2.417
  • Lustre Adamantine
  • Crystal System Cubic
  • Transparency Transparent
  • Chemical Formula C
  • Composition Carbon


Diamond mine map

Although South Africa is still a major supplier of Diamonds, today it holds less than 50% of the market share, and it cannot control the market as much as it once did. These days, the big players on the scene also include India, Canada, Russia, Australia and Brazil.

There are a handful of other countries around the world that also contribute to the supply chain of Diamonds, many of which are also in the southern part of the African continent. Let's take a look at some different types of Diamonds and jewellery designs.


Diamond Engagement Rings

Even if you only ever buy or own one Diamond ring, chances are it will be an engagement ring. We've already touched on how Diamond came to be so closely associated with engagement rings, but the simple fact is that Diamond is the toughest mineral known to man.

For most, an engagement ring will be worn every single day for the rest of their lives. Diamond is a 10 on the Mohs hardness scale, and Sapphire and Ruby - the next hardest stones - are a 9. What the Mohs scale doesn't tell us, though, is that Diamond is actually four times harder than Ruby and Sapphire.

As a stone that's going to take all the knocks, scrapes and scratches that come with living our lives, Diamond is very much up to the job. But, if you have your heart set on a coloured gemstone engagement ring, don't let this stop you.

For more help and guidance, read our blog on how to choose an engagement ring.

Diamonds in Silver

The days of Diamonds being exclusively reserved for the royal, rich and famous are long gone. Diamond mining is a lot more open than it used to be, and more Diamonds flow into the market in many different grades and from many different locations, which has brought the price down to much more reasonable levels for the gem.

If you want a more affordable Diamond ring to add to your collection we have a wonderful range of designs, including some with coloured Diamonds in them. The great thing about setting Diamonds in Sterling Silver is that, much like White Gold, it emphasises and complements the sparkle and brilliance of White Diamond, and allows the hue of coloured Diamonds to really pop.

Coloured Diamonds

Diamonds actually come in a whole range of colours, although naturally coloured Diamonds are exceedingly rare and sought after. When judging the all-important characteristics of coloured Diamonds, we still adhere to the 4Cs. However, when assessing fancy coloured Diamonds the colour becomes the defining factor, and the slightest colour differences can impact the value of a coloured Diamond significantly.

The most valuable hues are pink, red, blue and green. If a naturally coloured Diamond is out of your price range but you adore the look and wish to own one, there are widely used techniques and treatments for adding colour to White Diamonds. We strive to bring you the finest coloured Diamonds from all over the world; unlike some of our competitors we offer full disclosure, so when choosing your Diamond you will always know whether or not it has been enhanced to bring out the Diamond’s full potential.

Explore our coloured Diamonds blog for more information on how to choose yours.

Rough Diamond


Diamond is a hard gemstone, so you can clean it with little worry using warm soapy water and a small brush. Most are suitable for ultrasonic and steam cleaning too, but be sure your stone doesn't have any treatments, severe inclusions or fissures before opting for either of these two methods.

Remember that whilst the Diamond will withstand these tougher jewellery cleaning methods, will the setting or the other gems in your piece? Always clean jewellery in line with the most delicate element of the piece.


Caring for Diamond jewellery is mostly about keeping it separate from your other pieces. Diamond will scratch any other gemstone because it's top of the hardness mountain. Keep each Diamond piece separate too, to stop them damaging each other. Keep them in individual soft pouches or boxes if possible. It's still best to remove Diamonds before doing any household work, exercise or sports.


Diamond Rings

Diamond is a timeless classic that every gem collector must surely want to own? As much as we all want the 5ct Diamond solitaire ring in Platinum, there are endless options for gorgeous, stylish, classic and meaningful Diamond jewellery designs, and we're sure you'll find the perfect piece for you here at Gemporia.

Below are some links to get you started, and you can narrow your search further by using the options on the left hand side of these pages.

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