DIAMONDS

FORMATION & CHARACTERISTIC

Diamonds are formed over 3.3 billion years ago, 200km below the Earth’s surface. Under conditions of intense heat (900 to 1,300 degrees Celsius) and pressure (between 45 and 60 kilo-bars), carbon atoms crystallise, forming diamonds. It takes millions of years for a diamond to form, and geologists believe the most recently formed diamonds may be up to 45 million years old.

Molten kimberlite (also known as magma) are also formed within the Earth’s upper mantle under conditions of intense heat and pressure causing it to expand at a rapid rate. This expansion causes the magma to erupt, forcing it into the Earth’s surface and taking along with it the diamond-bearing rocks. These types of “eruptions” have not occurred in recent times, and it is believed that they happened during a time when the Earth was naturally hotter, thus making such eruptions more likely. Traveling at an incredible speed, the erupted magma forms a pipe to the surface of the Earth. As the magma cools, it hardens to form a rock called Kimberlite, the most significant source of diamonds. The Kimberlite settles in vertical structures known as Kimberlite pipes.

Kimberlite derives its name from the town of Kimberley in South Africa, where the first diamonds were found in this type of rock. Though Kimberlite pipes are the most significant source of diamonds, it is estimated that only 1 in 200 Kimberlite pipes contain gem-quality diamonds. This is testimony to the rarity of diamonds, and serves as a reminder that a diamond is a unique gift from Mother Nature, unrushed in its formation, and extremely valuable due to its scarcity.

Diamonds are mined by means of various techniques, and on average, 250 tonnes of ore are mined to produce a one carat gem-quality polished diamond. 

The word “diamond” comes from the Greek word “Adamas,” meaning “indestructible.” The strongest material known to man, a diamond consists purely of carbon, making it the only gem comprising of a single element (it consists of 99.95% carbon). The remaining 0.5% is believed to consist of trace elements, which can have an effect on the colour of a diamond, but are not a part of its chemical structure or molecular make-up. Found in abundance, carbon takes on many forms: the difference between a diamond and a lump of coal, is essentially their molecular structures.

DIAMOND HISTORY

The world’s love of diamonds had its start in India, where diamonds were gathered from the country’s rivers and streams. Some historians estimate that India was trading in diamonds as early as the fourth century BC. The country’s resources yielded limited quantities for an equally limited market: India’s very wealthy classes. Gradually, though, this changed. Indian diamonds found their way, along with other exotic merchandise, to Western Europe in the caravans that travelled to Venice’s medieval markets. By the 1400s, diamonds were becoming fashionable accessories for Europe’s elite.

In the early 1700s, as India’s diamond supplies began to decline, Brazil emerged as an important source. Diamonds were discovered in the pans of gold miners as they sifted through the gravels of local rivers. Once it reached its full potential, Brazil dominated the diamond market for more than 150 years.

While sources changed, the diamond market experienced its own evolution. The old ruling classes—diamonds’ biggest consumers—were in decline by the late 1700s. Political upheavals like the French Revolution led to changes in the distribution of wealth.

The 1800s brought increasing affluence to western Europe and the United States. Explorers unearthed the first great South African diamond deposits in the late 1800s just as diamond demand broadened.

The story of the modern diamond market really begins on the African continent, with the 1866 discovery of diamonds in Kimberley, South Africa. Entrepreneur Cecil Rhodes established De Beers Consolidated Mines Limited 22 years later, in 1888. By 1900, De Beers, through its mines in South Africa, controlled an estimated 90 percent of the world’s production of rough diamonds.

The South African sources affected many segments of the diamond industry. This was especially true as diamond mining moved from the surface to farther underground. Because of the huge costs and comparatively low yields involved, the new sources forced the development of more efficient mining techniques. They created the need for better marketing. They also led to advances in cutting and polishing—advances that increased efficiency, reduced costs, and enhanced the appearance of finished stones.

In the 1870s, annual production of rough diamond was well under a million carats. By the 1920s, the figure was around three million carats. Fifty years later, annual production approached 50 million carats, and in the 1990s it surpassed 100 million carats per year.

At the end of the 1970s, the world’s most important rough diamond producers were South Africa, Zaire (now renamed the Democratic Republic of Congo), and the former Soviet Union. In the 1980s, output of higher-quality diamonds from Russia and South Africa remained relatively constant, but Zaire’s production of lower-quality diamonds more than doubled.

In 1982, a highly productive new mine in Botswana added to world production. A prolific source of high-quality diamonds, the Jwaneng mine boosted Botswana’s production so much that the country rose to third in the world in total diamond recovery, and second in diamond value. De Beers contracted with Botswana’s government to buy the mine’s production and Botswana set out to build its own diamond-cutting industry.

World diamond mining expanded dramatically with the discovery of sources in Australia in 1985 and important new deposits in northern Canada in 2000.

The market probably changed as much after 1990 as it did in the years after the 1866 discovery of diamonds in South Africa and the establishment of De Beers. The 1990s brought exciting new sources and encouraged the dramatic growth of some cutting centers. All this was happening as the world economy fluctuated wildly.

As one of the trade’s major participants, De Beers had to change, too. The De Beers of today bears little resemblance to the De Beers of 1989. The company greatly reduced its role as the custodian of diamond supply. Instead of flowing into the market in a single-channel path from De Beers, diamonds now flow into the market through multiple channels.

Not everything changed, though. Regardless of the path they take, diamonds still flow from mines through cutting centers, and ultimately to retail customers.

Diamond’s splendour has been appreciated for centuries, but there was not much scientific knowledge about it before the twentieth century. Since then, diamond knowledge has grown steadily, with research by chemists, physicists, geologists, mineralogists, and oceanographers. In the past 50 years alone, scientists have learned a lot about how diamonds form and how they’re transported to the earth’s surface. That knowledge has made it easier to predict locations for new diamond discoveries.

KIMBERLEY PROCESS

The Kimberley Process ensures that every member adheres to regulations to make sure that diamonds have been traded throughout the supply chain in a fair and ethical manner. These strict, industry-led principles and processes have resulted in transparency and accountability; far more so than in other industries such as the textiles and coffee.

When buying a diamond from a respected retailer with the proper documentation, you can be assured that your diamond is conflict-free.

When diamonds are mined in an ethical manner and in a conflict-free environment, the economic and social benefit is of great value. Currently, over 10 million people are employed directly in the diamond trade for mining, polishing, distribution and retail. The socioeconomic impact has changed the lives of many in Namibia, Botswana, Angola, South Africa, Russia, Canada and other major diamond producing countries.

GRADING – 4C’S

All diamonds are unique and there are no two diamonds are the same, which is just part of what makes this glittering gem so spectacular. From its formation deep within the Earth’s crust billions of years ago, to the moment you showcase its beauty in the form of a stunning jewellery creation, there are four things to consider when it comes to what truly differentiates one diamond from another, namely the 4Cs – Cut, Colour, Clarity and Carat Weight.

CUT

A diamond’s cut is one of the most important (and visual) aspects to consider when grading a diamond, as it directly determines the diamond’s fire, brilliance and scintillation. Often confused with a diamond’s shape (round, princess, emerald, cushion, etc.); the cut of a diamond refers to how well the diamond has been cut and polished, regardless of its final shape.

When you choosing a diamond, have a look at the diamond certificate, which will state how the cut has been graded. A round brilliant cut diamond (the most popular diamond cut) is graded in the form of Excellent, Very Good, Good, Fair or Poor.

COLOUR

Interestingly, the diamond color evaluation of most gem-quality diamonds is based on the absence of color. A chemically pure and structurally perfect diamond has no hue, like a drop of pure water, and consequently, a higher value. D-to-Z diamond color-grading system measures the degree of colorlessness by comparing a stone under controlled lighting and precise viewing conditions to ‘masterstones’ of established color value.

Many of these diamond color distinctions are so subtle that they are invisible to the untrained eye; however, these distinctions make a very big difference in diamond quality and price.

FANCY COLOUR

Diamonds in the normal color range are colorless through light yellow and are described using the industry’s D-to-Z color-grading scale. Fancy color diamonds, on the other hand, are yellow and brown diamonds that exhibit color beyond the Z range, or diamonds that exhibit any other color face-up. These rare specimens come in every color of the spectrum, including, most importantly, blue, green, pink, and red.

Gem diamonds in the D-to-Z range usually decrease in value as the color becomes more obvious. Just the opposite happens with fancy color diamonds: Their value generally increases with the strength and purity of the color. Large, vivid fancy color diamonds are extremely rare and very valuable. However, many fancy diamond colors are muted rather than pure and strong.

CLARITY

For a better understanding of diamond clarity, we have to refer to the creation of diamonds. Natural diamonds are the result of carbon exposed to tremendous heat and pressure deep in the earth. This process can result in a variety of internal characteristics called ‘inclusions’ and external characteristics called ‘blemishes.’

Evaluating diamond clarity involves determining the number, size, relief, nature, and position of these characteristics, as well as how these affect the overall appearance of the stone. If you are trying to determine what is the best clarity for a diamond, remember that no diamond is perfectly pure. But the closer it comes to purity, the better its clarity.

The Diamond Clarity Scale has 6 categories, some of which are divided, for a total of 11 specific grades.

• • Flawless (FL) No inclusions and no blemishes visible under 10x magnification
  • Internally Flawless (IF) No inclusions visible under 10x magnification
  • Very, Very Slightly Included (VVS1 and VVS2) Inclusions so slight they are difficult for a skilled grader to see under 10x magnification
  • Very Slightly Included (VS1 and VS2) Inclusions are observed with effort under 10x magnification, but can be characterized as minor
  • Slightly Included (SI1 and SI2) Inclusions are noticeable under 10x magnification
  • Included (I1, I2, and I3) Inclusions are obvious under 10x magnification which may affect transparency and brilliance

CARAT

The Carat is the standard unit of weight used for diamonds. 1 carat = 0.2 gram, or 200 milligrams. Each carat is subdivided into 100 ‘points.’ This allows very precise measurements to the hundredth decimal place.

The higher the carat, the more rare and more valuable the diamond. However, the Clarity, Colour and Cut is also important for the evaluation.

CERTIFICATION

Before being graded, most diamonds are sent to a diamond grading laboratory for a comprehensive evaluation. This process is known as certification. The certificate is a formal document which details the characteristics of the diamonds, especially its cut, carat, colour and clarity, and may also include its finish (polish and symmetry), fluorescence and other additional comments.

Diamond grading is carried out under controlled environment, using the latest technology, to ensure that the 4Cs are accurately and fairy evaluated. Each diamond certificate has a unique number on it which corresponds to one particular diamond. Once certification is complete, the diamond along with its certificate, is ready to be sold or set into beautiful jewellery creations. This certificate assures the buyer that the diamond truly has the characteristics that the sales executive says it does.

The certification laboratories which are accepted and recognized worldwide are:

1. GIA – Gemological Institute of America
2. AGS – American Gem Society
3. IGI – International Gemological Institute
4. EGL – European Gemological Laboratory
5. HRD – Hoge Raad voor Diamond