THE DIAMOND

This is a brief and unapologetically enthusiastic introduction to the wonderful world of the diamond and diamond Jewellery. It's intended to provide you with enough information to hopefully increase your appreciation of these gems and to help you make good buying decisions. For a more detailed study of the subject there are some links to books, information and web sites at the end of this guide. In the meantime, let me loose and let's get started and take a closer look at those sparkling and valuable gems!

A diamond is the rarest expression of one of the simplest and most common elements on earth, namely Carbon. You and all of life on earth is classified as carbon-based and this element is in your body, the air you breathe, the food you eat and the ground you walk upon. In one of its common forms you'd recognise carbon as lumps of coal! (In case you are wondering, or are a trained geologist about to test me the most common chemical component occuring in the earth's crust is, in fact, Silica (SiO2). The simplest silicate is Quartz).

The Diamond technical bit: Moh's Hardness: 10 More about this later!), Specific Gravity: 3.516 - 3.525, Crystal System: Isometric occuring as Cubes, Octohedra and Dodecahedra - octohedra crystals most commonly used for gems, Lustre: Adamantine to Greasy, Cleavage: Octohedral, Fracture: Conchoidal.

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ORIGINS
The accepted view is that most diamonds were formed approximateley 3.3 billion years ago below the earth's surface (around 60 miles down) in the boiling magma (molten rock and minerals). This is where the high temperature and crushing pressure transformed simple carbon into its crystalline form we call diamond. At some point the earth vented the magma towards the surface through volcanic eruptions bringing the diamond crystals within man's reach. As the magma (lava) cooled the diamonds were locked into the columns of solid kimberlite or lamproite which we call 'pipes' and it's these pipes that are mined today for their rare and precious cargo.

The most famous diamond producing area is South Africa where the first diamond find was reported in 1866. Alluvial dimaonds have been found throughout the USA, the largest North American find weighed a modestly impressive 40.23 carats and was found in Arkansas. North western Australia (the Kimberley district) produces diamonds but these are generally quite small stones and usually coloured (mainly yellows). The most legendary of diamonds were discovered in the Golconda area of southern India and include the Koh-I Nor and the Jehangir daimonds. Some good quality diamonds are also found throughout Brazil and just recently there have been diamond finds in Russia.

Just for the record the world's largest rough diamonds (that's the uncut crystal) include, at No1 slot, The Cullinan (3,106 carats) followed in size order by Excelsior (995.20 carats), Star of S Leone (968.90 carats), The Incomparable (890.00 carats) and Woyie River (770.00 carats). By the way, The Cullinan was studied, cleaved, cut and polished into a number of gem diamonds, two of these (one is called 'The Great Star of Africa' it has 74 facets,is pear shaped and weighs 530.20 carats) reside in The British Crown Jewels.

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DIAMONDS ARE FOREVER
The natural diamond crystals we mine from the volcanic pipes vary tremendously in size, shape, colour and transparency. However they all share one very important characteristic - they are the hardest known natural substance on earth.

On Mohs' scale of relative hardness (Freidrich Mohs 1773-1839) the diamond scores the maximum ten. However, the scale is a little misleading in that the next 'hardest' at 9 on the scale is Corundum (in gems that is the sapphire). But if we translate the Mohs scale into something more detailed in the form of the Rosiwal Grinding Hardness scale (August Karl Rosiwal 1860-1923) then Corundum at 9 rates 1,000 but diamond at 10 rates 140,000. So although the 'next hardest' gem to diamond is the sapphire, the diamond is, in fact, 140 times harder!

In other words, the only thing that can scratch a diamond (either as a rough crystal or as a finished gemstone) is another diamond! That's probably one reason why we have the saying "diamonds are forever" because a diamond, once formed 3 billion years ago, remains completely unchanged. Unchanged by time and nature until man applies his ingenuity and artristry to bring out the diamond's secret - when cut and polished, a diamond reveals colourful 'fire' and brilliance unmatched by any other natural gemstone.

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THE GIFT OF LOVE
These days it seems quite natural for us to signify our love and commitment through the gift of diamonds in the form of engagement and eternity rings, and to adorn our loved ones (and ourselves!) with a wide variety of diamond Jewellery. As I write these words on my trusty iBook G4 I am wearing a Cartier Santos 100 with a diamond set case and bezel. Like many men today, I enjoy wearing diamonds and having access to them. However it wasn't always so. History shows that diamonds were exclusively reserved for royalty until around the 15th century and until then were seen as symbols of power and invincibility. This is interesting as the word Diamond comes from the Greek "Adamas" meaning "unconquerable".

The origins of the engagement ring have been traced to the 15th century in Austria. It was here, in the year 1477, that Archduke Maximillian sealed the arrangement to marry Mary of Burgundy by the gift of a gold signet set with diamonds in the form of the initial "M". You might also wonder why we seem to have established a particular finger for ladies to wear their engagement ring upon. This tradition seems to go back to the kingdom of ancient Egypt. The ancient Egyptians had quite advanced theories of medicine and magick and one of their beliefs held that the "vein of Love" ran through the third finger of the left hand directly connecting it to the heart.

In passing, you might wonder at the tradition of the eternity ring. The ring is a circle which, as the wording in some church wedding services reminds us, signifies something withouit end. The ring therefore is symbolic of love that has no end and is therefore for eternity. Giving a diamond eternity ring for commemorating a significant anniversary is a beautiful and lasting expression of undying love. Yes, I'm a romantic at heart!

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SORRY GUYS, SIZE DOES MATTER!
As a naturally occuring material, diamond is found in a wide range of sizes. Diamonds are valuable because only a small amount of the total produced by nature have ever reached the earth's surface. Of those diamond crystals that are mined many are not suitable for cutting and polishing as gems and are, instead, used in industry where their extreme hardness is ideal for cutting and polishing tools.

Even those stones that are deemed suitable for cutting and polishing have a lot of 'waste' that the cutters will have to discard. Quite a large amount of the native crystal will be cut away as smaller stones or industrial abriasive to avoid the faults and inclusions that would make the finished gem to low in clarity and possible colour. Of all the stones deemed suitable for use as Jewellery, only around 5% will be above 1 carat (100pts/0.2 gram) in weight. Approximately 250 tons of kimberlite/lamproite ore must be mined and processed to produce one carat of polished diamond at gem quality. So in the case of gem diamonds the old adage is absolutely true; Big IS beautiful!

So you may comment that the average high street is full of diamonds in umpteen shop windows these days, and up to a point you'd be right. However, take a closer look and you'll discover that by far the majority are small and well below even 0.33 carats. Try finding stones above one carat and you will see that they are far rarer. To understand how we calculate the size of a diamond please refer to the Carat Weight explanation later in this article.

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THE FOUR Cs
Once a diamond crystal has been cut and polished to create a recognisable diamond gem the variations mentioned earlier will still be noticeable to some extent and will have an effect on the stone's market value. In order to have consistency in valuation diamonds are 'graded' according to very tightly defined parameters. In the Jewellery trade a diamond's 'grade' is defined by what we call 'The Four Cs' and these are Cut, Colour, Clarity and Carat weight. Hopefully after reading this article you will also have a fifth 'C' at your service, meaning "Confidence" in your ability to select and discuss your diamond purchases with a reputable jeweller!

So let's have a quick look at these four Cs, starting with the interesting one of Cut.

CUT
Of the 4Cs cut is the one where the skill and ingenuity of man comes into it's own. The other three Cs are dictated by nature and were set in stone (literally) 3 billion years ago. The cut is what brings the diamond to life by making as much advantage as possible of the diamond's refractive and reflective properties. When a diamond is cut to precise angles and proportions light enters the stone and is reflected and refracted from internally one facet to another and then is released (dispersed) through the top facet which is called the crown.

A badly cut diamond is one where the angles are just a little too shallow or steep and the light then escapes through the sides or bottom before being reflected. The end result is that such a stone will lack the sparkle, brilliance and fire (colours of the spectrum) of a well-cut one. So a diamond that has good colour, clarity and carat weight is still totally dependent on the cutter and polisher's skills to release it's full beauty. So here, for your information dear reader, are the seven most recognised cuts of diamond:

Please Note that there are other 'proprietary' cuts of diamonds on sale that have been developed and marketed as exclusives by retailers such as Goldsmiths Group's "Millennium".

COLOUR
Although you will normally only see diamonds that appear to be colourless or white in themselves, natural diamonds come out of the ground in a surprising range of colours. As the beauty of a diamond depends on the effects of light and the cut's ability to split the light into the colours of the spectrum, some natural diamond colours do not lend themselves to being transformed into Jewellery.

The most common colorations are in the yellows, greys and browns. Sometimes the converted carbon stays entirely black and you have a black diamond. However, some rarer colours of natural diamond can add to the value of the finished gem. The rarer colours are blues, oranges, and greens.

For general guidance the whiter (colourless) the diamond, the better it is and it's selling price will reflect (!) this factor accordingly. For this reason we grade the colour of diamonds from colourless white through to distinctly yellow by means of an alphabetical scale. Although grading is a science in simplest terms for the customer we can understand this scale as follows:

Other colours are certified as 'fancies' but are pretty rare to find in your average high street jewellers. The most famous perhaps of the fancy coloured diamonds is the 'Blue Hope' once owned by Louis XIV and purchased in 1930 by Henry Philip Hope who gave it its current name. It now is on display at the Smithsonian Institute in Washington, USA where this 45.52 carats blue diamond has become famous.

CLARITY
As a natural product of nature cooked up, as we learned earlier, in a boiling soup of molten rock and minerals some 3.3 billion years ago, it is not surprising that almost all diamonds contain inclusions and faults. These inclusions are often quite small particles of black carbon left over from the magical conversion of raw carbon into diamond. The small black particle inclusions are often not visible to the naked eye - and spread around the crystal. Some natural faults or flaws in the crystal structure appear as milky veils inside the stone that can also include black carbon particles.

This is where the cutter's art of studying the rough stones thoroughly from all angles and at various powers of magnification pays off. By being acutley aware of the inlcusions and plotting them in three dimensions the cutter can begin shaping the finished gem so as to avoid some inclusions and position others in the finished cut. However, let's be clear about this, inclusions are a natural feature of diamonds and can be likened to fingerprints making each stone unique. The fewer inclusions there are in a finished gem the rarer that gem becomes, but the position, size and nature of the remaining few inclusions make the gem unique. I like that thought, my diamond in my signet ring is unique with no other diamond on earth quite like it!

The clarity of a diamond is graded just as with the other Cs. There are currently three accepted systems of classifying diamond colour namely GIA, HRD and CIBJO. An international (ISO) standard is being established but for now the three are the major grading sytems in use. For the customer the easiest way to understand the clarity of a diamond is from the letters and numbers that relate to the chart here:

So that's three of the four Cs and, if you're still with me and haven't given up hope, here's the last one!

CARAT WEIGHT
All precious gemstones share a common system for understanding the size of the gem by measuring the actual weight of the finished gem. The size of a diamond or any precious gem is defined by its weight in carats or points of a carat. Please note the word "carat" can be seen in regular use in reference to the purity of gold but in that case the word has an entirely different meaning. In diamond terms carat is a word that derives from an ancient unit of weight, namely the seed of the carob tree. If you are wondering the Carob tree is remarkable in that ALL its seeds are always uniform in weight and size and so provided the ancient traders with a reliable and constant reference. Today with our weights and measures standards we have defined one carat as 0.2 grams (one fifth of a gram) and divided this into 100 points. So a diamond of 25 points would be also expressed as 0.25 (one quarter) of a carat.

The reason for defining the size of a gem by it's weight rather than, say, by how many millimeters it is across and top to bottom is quite simple. The CUT of a diamond or other stone may give it an apparent size that doesn't actually reflect the depth of the stone and the total mass of gem present. A stone of 1 carat in each of the seven most commonly used cuts (see above) will present, once mounted, a surprising variation in its apparent size!

As stated earlier the larger a diamond is in carats weight, the rarer it is. This rareness increases in relation to the increasing carat size so a diamond of 6 carats would be consdierably rarer than one of 2 carats and this will be reflected in the pricing. We price diamonds in £/$ per carat and the price per carat increases with the size of the stone, so a stone that weighed 2 carats will cost less per carat than a stone at 6 carats will.

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THE LAST WORD FROM THE AUTHOR
So there you have it, a crash course on the subject of those wonderful gems we call diamonds. I did my best to not get too detailed but to give you some idea of how fascinating diamonds can be. Please have a look at the links to various diamond-related information. Hopefully you will find the information I have provided at best useful and at least an interesting read. I want to just add a note of caution now dear browser. I want to raise my 'pet peeve' of the moment on the matter of diamond 'certfication' and offer words of caution (and hopefully, wisdom).

There has been a trend of late for certain high street jewellers to promote their diamond rings through presenting them on display along with certification of the stones. Now it's true that diamond certification by such bodies as GIA, HRD, IGI and CIBJO is a valuable aid if you are buying diamonds as investments. A loose investment stone's value will be set in relation to the 4Cs and the certification provides an objective evaluation of the stone against those criteria which a future purchaser will accept as a pricing formula.

However, if you are buying a loved one an engagement ring you are supposed to be buying with your heart not your bank manager's brain! You don't buy a ring for your beloved on the basis of how much you could get back later if you resell it. You buy it for its beauty and because she will treasure it and wear it for a lifetime (we hope). So what's the point of 'certificated' diamond rings on sale? Well perhaps you could say the certificates are there to give you confidence that the rings and diamonds are good value? Hmmm, unless you work closely with diamonds and loose gems regularly, and understand precious metal values, you quite frankly haven't a snowflake in hell's chance of equating 'J(2), Brilliant (good), S12, 0.77cts' to the price tag.
Any jeweller can certify any diamond by paying the fee and submitting it to the relevant body. If it comes back as 'J(4),Brilliant, P3, 0.85cts' then it's a certificated gemstone -but it is a low quality stone and might be better of in a drill bit! I have had certificated rings brought in to me for valuation for insurance purposes and, when the valuation didn't reach the client's expectations for a certficated stone, had to explain to the client that the certificate simply confirmed that the stone was imperfect not that it was valuable.

So by all means look at and consider purchasing a ring that has certifcated stones if you like the ring and you understand what the certficate is saying to you. The explanations of the 4Cs above should go some way to helping you. Feel free to print them off and take them with you for reference. Deal with jewellers who you trust and who understand the importance of the purchase to you/your loved one. Insuring any diamond Jewellery is, in this day and age, sadly a sensible thing to do, so by all means ask your jeweller to provide you with enough information to register the gem with your insurers.

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