Buying a Significant Diamond

“Buying a significant diamond will be one of the most moments of your life. Most likely it will accompany one of your lifes top four of five milestones and will be shown of thousands of times to anyone from your near and dear to strangers in the street.  So how to buy a truly beautiful diamond?”

It is something that Chris and Tim Holdsworth have been learning for two decades, and something they learned from three previous generations of family jewellers. There is a science and an art to it and choosing beautiful diamonds needs attention to both.

This article will provide you advice on choosing a beautiful diamond that is the best value for you. Our recommendation is to do as much research as you can or simply come in and see us. The human eye is what determines a beautiful diamond – what is written on a diamond report is a rather feeble attempt to describe what the eye can already see.

Know your C’s

The Gemological Institute of America invented a system for grading diamonds. You probably know it as the 4C’s.
Carat – The weight, related to the size of a diamond
Clarity – Size, amount and obviousness of inclusions
Colour – The lack of body colour
Cut – Brilliance, Fire, Sparkle and Scintillation

Carat – Diamonds and other gemstones are weighed in metric carats: one carat is equal to 0.2 grams, about the same weight as a paperclip. Just as a dollar is divided into 100 cents, a carat is divided into 100 points. For example a 50-point diamond weights .50 carats or ‘half a carat’.

Clarity – The GIA Clarity Scale contains 11 grades, with most diamonds falling into the VS (very slightly included) or SI (slightly included) categories. In determining a clarity grade, the GIA considers size, nature, position, colour on relief, and quantity of clarity characteristics visible under 10 x magnification.

Colour – Diamond colour is all about what you can’t see! The highest and most valuable grading is for colourless diamonds, with the grading dropping as colour becomes more visible. The grading starts with the letter D (being the most colourless), working its way down the alphabet. You will generally see hints of yellow and brown as the grade drops.

Cut – Cut is what fuels a diamond’s fie, sparkle and scintillation. Each of the 58 facets on a traditional round brilliant cut diamond are precisely defied and it is the job of the cutter to apply each facet to pinpoint precision. The allure of a particular diamond depends more on cut than anything else.

Our Equation

Knowing the four C’s gives you some technical details, but it doesn’t help your personal choice in choosing the best diamond for you. We prefer to break it down to a simple diamond equation.

Budget plus…

You probably have an idea of what you would like to spend on a diamond and it may seem counter intuitive, but let’s start by ignoring cut and carat. For the importance of it, cut makes surprisingly little difference to a diamond price. The carat size you would like will end up being determined depending on your choices of clarity and colour with your budget.

Clarity plus…

Do not choose anything lower than Si2. Choosing Vs or higher is a personal choice. If you peer into a diamond with a jewellers magnifying lens you may be able to see inclusions in an Si1 or Si2 diamond however you won’t see them with your naked eye. For diamonds graded Vs2 and above you will never see the inclusions, even if a jeweller shows you where to look with a lens. Hours of practice are needed to spot them.


Do not choose anything lower than H. Unless you look at the diamond from underneath you will struggle to see the difference between a D and F colour. Perhaps you can discern a D and G, perhaps not. But below an H and you will notice a colour tinge, yellow or grey most likely.

…equals Carat

Combining your budget, colour and clarity will yield a carat size that fits your desires.

None of the above are difficult. Diamond grading laboratories provide all of this information for you and diamonds over 0.30ct have a report which helps you easily compare them. The skill of diamond buying is in the cut.

Read on to Part 2 that upgrades your diamond for free!

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