Natural diamonds were formed under immense tectonic pressure over 3 billion years ago, when the earth was only a third of the age it is today. Their earliest documented discovery by humans was in southern Asia over 6 millennia ago, although they may actually have been found much earlier. Diamonds feature in the historical texts, poetry and mythology of all the great civilisations of antiquity, including the Romans, Greeks, Egyptians, Persians and Babylonians. This reverence continued through the Middle Ages where people often believed diamonds to have mystical healing properties and powers. Diamonds and other precious gemstones are known to have adorned royalty for many centuries and they have been present in European crown jewels for over 2,300 years. Surprisingly cutting and polishing diamonds into symmetrical geometric shapes was not possible until Venetian craftsmen developed the techniques necessary to achieve this around the eleventh century AD. The use of diamond engagement rings can be traced back to ancient times but the widespread adoption of this practice began with the proposal of Archduke Maximillian of Austria to Princess Mary of Burgundy in 1477.
(Diamonds have been cut and polished into intricate geometric shapes since the early Renaissance)
Diamonds are formed from a dense concentration of carbon atoms that form a distinctive and uniquely dense "diamond lattice" crystal. With the highest possible 'Mohs' hardness score of 10, they are the hardest material on the planet. The vast majority of diamonds are the colourless or white variety, while trace elements or impurities in around 1 in 10,000 carats of rough stones mined create coloured rare fancy coloured stones. Fancy coloured diamonds come in many colours, including yellow, brown, orange, green and gray but the most valuable of all are red, closely followed by pink and blue. Almost any combination of the above are also possible (see a more detailed description in our earlier article: Fancy coloured diamonds & the 4 'C's - everything you need to know). The etymology of the word diamond is thought to originate with the ancient Greek adámas, which appropriately translates into modern English as "unbreakable." Diamonds are found in every continent on earth but some of the most prolific diamond producing nations include: Australia; Canada; South Africa; Botswana; Russia and India.
(Fancy coloured diamonds cover the entire spectrum)
Many tonnes of earth and rock must be moved in order to produce each carat of cut and polished diamond and over 80% of all production ends up in industrial rather than jewellery uses. Most diamonds are sorted, cut and polished by hand in a very labour and time intensive process that has resulted in countries with the lowest wages, most notably India, gaining a competitive advantage. In recent years the ethics of the diamond industry has come under increasing scrutiny and the demand for certified 'conflict' free non 'blood' diamonds has risen significantly. In 2000 the United Nations agreed the Kimberley Process with the principle diamond producing nations in an effort to stem the tide of conflict diamonds entering the market place, with somewhat mixed success. The only way to be certain of the ethical provenance of a diamond is by determining it's country of origin - nations such as Australia, Canada, Botswana and South Africa, for example, are stable pluralist democracies with good human rights and labour welfare records.
(The Kimberley Process was set up in 2000 in an attempt to stem the flow of 'conflict' diamonds)
Diamonds are the birth stone of the month of April and they have been regarded as a symbol of enduring love for many centuries, which accounts for their prevalence as engagement ring centre stones. Diamond is also associated with the 60th anniversary year, such as the Diamond Jubilee of Queen Elizabeth II in 2012. Many famous diamonds have a strong royal connection, including the Cullinan diamond, sometimes referred to as the 'Star of Africa,' which now forms part of the British Crown Jewells. It was discovered in South Africa in 1905 as a 3,106 carat rough stone, which was the largest ever produced up to that time. The 'Williamson' pink is another example of a royal stone, set into a broach it was presented to Queen Elizabeth as a 24 carat flawless pink diamond wedding present from the government of Tanganyika (modern Tanzania) in 1947.
(HM the Queen wearing the "Williamson" pink broach at her Diamond Jubilee in 2012)
When buying a diamond piece for someone always consider the person's tastes and style as well as the manner in which they intend to wear it. Diamonds can be very versatile: diamond rings, stud earrings, simple necklaces, pendants and bracelets can be worn on a daily basis. However consider the practicalities of large 'chandelier' and drop earrings and very large carat rings, as these may only be worn on special occasions. A diamond's value is determined by the famous "4 Cs" (cut, colour, clarity & carat) the higher the calibre of each, the greater the price. However many of the smaller increments can only be observed by a trained gemmologist and even then he or she may require a microscope to actually see them!
The cut of a diamond determines not only its shape but also the way in which it reflects light (enhanced by facets or flat surfaces) as well as the quality of workmanship that has gone into it. A highly competent cutter will maximise the 'sparkle' of a stone. Only buy stones that have a polish and symmetry grade of G (Good) VG (Very Good) or (Excellent) on their certificate.
(Some of the more popular diamond cuts)
"Loupe clean" stones, that is stones that are without inclusions visible under 10 X magnification, range from F (Flawless) to VVS2 (Very, Very Slightly Included) and are often indistinguishable from one another. Consider also "eye clean" or VS (Very Slightly included) stones (with no inclusions visible to the naked eye) as these can offer very good value for money. SI (Slightly Included) and I (Included) stones may contain inclusions visible to the naked eye.
(IF-VVS2 are 'Loupe' clean, VS1-VS2 are 'eye' clean, SI1-I3 contain inclusions visible to the naked eye)
Colourless diamonds are graded D-Z, where D is totally colourless and Z is heavily coloured (or 'yellowed'). A-C were deliberately left out in case 'whiter' than D stones were ever discovered, so far none have been found! The closer to D, the higher the value and when placed in combination with clarity, 'D-IF' (D colour, Internally Flawless) would be the most sought after. The difference between D, E & F colour is almost imperceptible to the naked human eye so this can be a useful way of reducing the cost of your purchase. With coloured stones (see our earlier article: Fancy coloured diamonds & the 4 'C's - everything you need to know) the deeper or more vivid the colour the rarer, and hence more valuable, the stone.
(White or colourless stones are graded by colour from D-Z)
Carat is simply the mass of a diamond, where one carat = 0.20 grams (approximately the weight of a paperclip). The price of a stone, all else being equal, will increase exponentially with carat size. As such a stone that is twice the carat of another may be many times its value. Diamonds also increase sharply in price when they cross certain key carat points, resulting in anomalies such as a 0.99 carat stone being worth significantly less than a 1.00 carat, despite being identical to the human eye.
(The value of a stone increases exponentially with carat weight)
Treated or Enhanced diamonds
There are a variety of methods of treating or enhancing a diamond, involving heat, chemicals, resins and oils. Any form of treatment will reduce the value of a diamond versus an identical non treated stone but that is not to say there is anything wrong with treated gems, providing the seller has been forthright in informing you of the treatment. Any good certificate will indicate if treatment has taken place and it is well worth studying this carefully before making a purchase.