5 facts you didn’t know about diamond cutting and polishing

Natural diamonds are the ultimate symbol of strength and resilience, prized possessions either bought to commemorate a special occasion or to be passed down from one generation to the next as family heirlooms. After the long process of polishing and cutting that rough diamonds go through before reaching a jewellery store near you, it is quite fitting that natural diamonds are considered unique and precious.

Finding rough diamonds

The first step after the diamond mining process is comminution where the ore is crushed and milled. Once the ore is crushed, the rough diamonds are separated from the slurry by passing it over a grease belt since diamonds are attracted to grease. The rough diamonds are then measured and sorted before the cutting and polishing process begins.

Natural diamond

Here are some lesser known facts about how to polish diamonds and diamond cut chart that you didn’t know:

  1. Return on Investment
  2. Natural diamonds have inherent emotional value for its buyer but for its manufacturer, the ROI trumps everything else. Each rough diamond is carefully and thoroughly examined before a decision is made on how it is to be cut. The diamond is then marked in a way that it yields the highest value.

    Natural diamond

    Based on the imperfections and the clarity it can yield, two to three diamonds can be marked from a single rough diamond.

  3. Diamond Cuts
  4. While colour, clarity and carat are the most recognizable criteria for selecting a diamond, a diamond cut chart can help you differentiate between a good diamond and a great diamond.

    Natural diamond

    Seeing a diamond cut chart you’d think that the fancy-looking heart shaped diamond would require more skill to cut and hence would be more expensive. But, the round diamonds command premium pricing, irrespective of carat!

  5. It takes a diamond to cut another diamond
  6. A specialized saw, which rotates at a speed of 4000 revolutions per minute, or laser is used to cut the rough diamond into different pieces. This process, called sawing, takes 4 to 8 hours.

    Natural diamond

    Interestingly enough, it is not the copper saw that cuts through the rough diamond but the diamond dust it is coated with. Since a diamond is the hardest known mineral to man, only another diamond can cut it.

  7. Making diamonds brilliant
  8. How to polish diamonds? In a process called brillianteering, the facets of the cut diamond are polished so that it reflects and refracts optimal amount of light. It is the polishing of the diamond that determines how much fire, brilliance and sparkle the diamond will have.

    Natural diamond

  9. All you need is some olive oil and diamond powder
  10. Scaif – a diamond cutting wheel – was invented in the late fifteenth century by a diamond cutter in Antwerp called Lodewyk van Berken. The scaif revolutionized the art of diamond cutting.

    Natural diamond

    The coating of oil and diamond powder ensured that the rough diamond wouldn’t shatter while cutting. Though the tools for cutting and polishing diamonds have become sophisticated over the years, a scaif is still used to bring out the brilliance of a diamond.
    Diamond cutting and how to polish diamonds is not only an art but a science as well. Not everyone can become a diamantaire – a person specializing in diamonds. It requires years of study and attention to detail. The process has little room for errors, thus only adding to the glory and enigma of the diamond – as it completes its long journey and transforms from a rough diamond to a brilliant jewel.

Image credit

  1. Alrosa
  2. Geology In
  3. AWDC
  4. Hearts on Fire
  5. Rio Tinto