The diamond standard

Auctioneer Jeremy Thornton looks at our fascination with diamonds – and how to pick out a real sparkler at the right price

Diamonds are the best-known and most sought-after gemstones in the world. The word ‘diamond’ comes from the Greek for ‘unbreakable’, and it is because of its hardness and ability to disperse light that it maintains that characteristic sparkle – reinforcing its status as a girl’s best friend. Diamonds are thought to have originated in India which remained the only major source of the gemstone until their discovery in Brazil in 1725. The modern era of diamond mining began in the 1860s in Kimberley, South Africa with the opening of the first large-scale diamond mine.


Today, annual global rough production is estimated at a mind-boggling 130 million carats with the majority of the world’s output making its way to Antwerp, the diamond capital of the world. Antwerp’s association with diamonds began in the late 15th century when the city’s highly skilled cutters developed a new technique to polish and shape the gems. And that leads me neatly onto the four C’s that go to make up a great diamond. These are Colour, Clarity, Carat and Cut. A gemologist has to learn to assess and measure the above as the combination of the four governs the final value of the stone. However, ultimately if the ring sparkles and has a bit of fire, it will sell. Colour is graded from D to Z, the most desirable being D’ to ‘F. This means it is colourless. G to J is near colourless, and so on down to the obviously dull stones. Clarity is determined by the amount of inclusions, or small visible specks, present in the stone. The rarest diamonds are categorised as FL (flawless) or IF (internally flawless) and contain no inclusions. VVS1 and VVS2 are very, very slightly included, then VS1 and VS2 are very slightly included, followed by I1, I2 and I3 which are full of visible inclusions. Carat is the unit which diamonds are measured in and is what many buyers consider of upmost importance when purchasing. Cut refers to the quality of the diamond cutter’s work and ranges from excellent, through to very good, good, fair and poor. Diamonds in modern engagement rings are predominantly round brilliant cut stones and, as the name implies, this cut adds that all-important sparkle. Other styles of cut you are likely to see include: emerald, Dutch rose, baguette, old European and princess, plus various shapes such as hearts and ovals.


When buying diamonds, personally I would focus on clarity and colour, so look for those assessed in the VS1 or even VVS2 clarity category and rated J or above for colour. But finally, as with most pieces of jewellery, it is the sentimentality which makes them truly priceless. Here in Birmingham, we are blessed with an excellent Jewellery Quarter, a real hidden gem in fact! I would encourage everyone to visit as there are auctioneers and quality craftsmen selling diamonds for everyone.