What Are Diamonds? Everything You Need To Know


What ARE Diamonds?

To understand the fundamentals of what a diamond is, it’s important to know of their origins. Where do the sparkly minerals that end up in our stores come from? Volcanoes. All diamonds are formed in the bowels of the Earth and forged under immense heat and pressure between 100 and 300 miles deep in the upper mantle. After brewing for billions of years, the crystals and various minerals surrounding them are sprung to the Earth’s surface during volcanic eruptions. The volcanic rock that diamonds are most regularly discovered in is kimberlite, but loose stones can be found in streams and rivers, having been washed out of the kimberlite. These are known as alluvial diamonds.

Where Are Diamonds Found?

Diamonds are therefore found where volcanoes are found, which has a huge geographical significance on where diamonds can be mined. Not all volcanic eruptions bring the gems to the Earth’s surface, but instead clusters of diamond producing volcanoes exist in twenty of the world’s countries. South Africa is now the fifth largest producer after Australia, the Democratic Republic of Congo, Botswana and Russia.


What Are Diamonds Made From?

Diamonds are made of pure carbon. Similarly, graphite is made of pure carbon, but the atoms are arranged in a completely different way to produce a soft substance. Diamonds, however, are the hardest known naturally occurring substance on the planet with a score of 10 on the Mohs hardness scale. Graphite, meanwhile registers at 1 on the Mohs scale, only just harder than talcum powder. The molecular structure of a diamond ensures it to be the hardest natural substance known to mankind.

How Big Are Diamonds In Their Natural Form?

The largest known diamond is a staggering 2,500 miles in diameter, weighing ten billion, trillion, trillion carats. We know what you’re thinking - why haven’t I seen a picture of this outrageous diamond? That’s because the stone is nestled away within a star - White Dwarf BPM 37093. Since the discovery of the diamond, the star has been nicknamed ‘Lucy’, after the Beatles Classic Lucy in the Sky With Diamonds.

According to astronomer Travis Metcalfe, of the Harvard-Smithsonian Center for Astrophysics, who led the team of researchers that discovered it, “You would need a jeweller's loupe the size of the Sun to grade this diamond,". Guess it’s not much bigger than Paris Hilton’s new rock then!

Back down on Earth, the size of diamonds isn’t quite so astronomical, but occasionally some staggering rocks are found. The world’s biggest diamond discovered is a whopping 3,106 carat stone, uncovered in South Africa in 1905. This was divided into smaller diamonds, the largest of which, The Star of Africa, adorns the Sovereign’s sceptre.

 Donald Bowers / Getty Images for Sotheby's

Donald Bowers / Getty Images for Sotheby's

 AP Photo / Seth Wenig

AP Photo / Seth Wenig

More recently, a tennis-ball-sized 1,109 carat diamond was discovered, and estimated to be auctioned for $70 million in 2016. In reality, the diamond failed to sell - what would you do with a tennis ball sized diamond? It was eventually sold to a British jeweller for a mere $53 million.When it comes to more wearable stones, the size of the average rough diamond found is less than 0.10 carats, which is a pretty petite stone. The stone would then sacrifice weight to achieve the optimum cut. It goes without saying that, the bigger the diamond, the rarer it is, and rarity adds to the value of a stone.

What Happens To A Diamond After Mining?

A diamond will usually undergo a 6 week period of travel and sorting. De Beers sort around 45% of the world’s diamonds, the rest going to sorting companies in Mumbai, Antwerp and Johannesburg. The diamonds will then be sorted for the most suitable purpose; only 20% of found diamonds are of high enough quality to be used for jewellery. The purer the diamond, the more suitable it will be for the jewellery industry, which prioritises stones with good colour and clarity. The remaining 80% of diamonds will likely be used for industrial purposes, for cutting machinery and so on. These will be the hard but less attractive stones among the lot.

The stones will then be cut to the optimum angles to achieve total internal reflection - pure sparkle. After cutting, diamonds will be graded by institutes such as the GIA, who consider the quality of cut, clarity, carat weight and colour of the stone - otherwise known as ‘The Four Cs’. The GIA inscribe a minuscule number on the stone for authentication purposes. At Queensmith, we’ll always show you the number, which can only be seen under 50 times magnification, and ensure this matches your GIA certificate.

Grown In The Lab

Whilst diamonds are the hardest naturally occurring substance, scientists in Germany managed to create something a little harder in the lab. The aggregated carbon nanorod (ANCR), was formed by superheating carbon molecules to 2,226°C and compressing to 200 times normal atmospheric pressure. Our Queensmith team is made up of certified gemologists, so we like to get a little geeky every now and again… Each molecule comprises sixty atoms that interweave in pentagonal or hexagonal shapes; they resemble tiny footballs. ANCR is so tough it would put Vinny Jones to shame, and can scratch a diamond effortlessly.

Today, consumers are becoming more interested in man made diamonds, or ‘cultured diamonds’. A very specific environment is simulated in a laboratory, consisting of extreme pressure and heat. Using the minuscule carbon seeds of existing diamonds and a whole lot of advanced technology, the carbon grows in the same way a natural diamond would. What’s your verdict, is a synthetically grown diamond as sentimental as a natural diamond?

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