No two diamonds are alike and the astute buyer needs to know what factors determine its value. Also, each buyer has a different need and budget. Prins & Prins will assist him/her in choosing the right one.

There are the 4 well known ie., Carat weight, Colour, Clarity and Cut that determine a diamond’s value. However, two other Cs , Certification and Confidence, also add value to a diamond.

1. Carat Weight
A carat is the unit used to weigh a diamond. The word “carat” is taken from the carob seeds that Arab gem traders once used as a counter balance to weight their gems. These little seeds weigh remarkably similar to within a few % of 200 milligram(0,2gm) which is the weight of 1 carat. Large diamonds are rare and have a greater value per carat. For that reason, the price of a diamond rises exponentionaly with its size.

What Size Diamond Should I Buy?

  • First, determine your budget, ie. what you comfortably can afford not what a jeweler tells you.
  • Deciding on carat size is really about striking a balance between size and quality. If she prefers larger jewellery, you can still find a larger diamond of very good quality by selecting one which is graded slightly lower in terms of color and clarity.
  • Think about what sort of setting you prefer. Our consultants will advise you on a setting that is in proportion with your diamond and with the size of her hand.
  • NOTE: Don’t confuse “carat weight” with “karat,” the method of determining the quality of gold.


2. Colour
When we speak of a diamond’s colour, we refer to the presence or absence of colour in white diamonds. Colour is a result of the presence of trace amounts of nitrogen, helium, etc., in the crystal structure of the diamond.

  • Because a colourless diamond, like a clear window, allows more light to pass through it than a coloured diamond, colourless diamonds emit more sparkle and fire. The formation process of a diamond ensures that only a few, rare diamonds are truly colorless. Thus the whiter a diamond’s color, the greater its value.
  • [NOTE: Fancy colour diamonds do not follow this rule. These diamonds, which are very rare and very expensive, can be any colour, from blue to green to bright yellow. They are actually more valuable for their colour. Black diamonds are not considered fancy and are relatively inexpensive.] To describe the colour of a diamond, most jewellers refer to GIA’s professional colour scale that begins with D(for colourless), and as the colour increases the colour grade goes down to Z, as does the value.

Which Colour Grade Should I Choose?
Diamonds graded D through F are naturally the most valuable and desirable because of their rarity. But you can still obtain very attractive diamonds that are graded slightly less than colourless. Diamonds graded G through I show virtually no color that is visible to the untrained eye.

A very, very faint hint of yellow will be apparent in diamonds graded J through M, this color can often be minimized by carefully selecting the right jewelry in which to mount your diamond. Keep in mind that, while most people strive to buy the most colorless diamond they can afford, there are many people who actually prefer the warmer glow of diamonds with a slight yellowish tint.

3. Clarity
Natural diamonds normally contain some inclusions and imperfections because they have grown under tremendous pressures in the vicinity of other minerals – unlike man-made diamonds that are created in a sterile laboratory.

Diamonds with no or few inclusions are more highly valued than those with less clarity because they are rarer.

How are diamonds graded for clarity?
Diamonds are graded for clarity under 10x loupe magnification. Grades range from Flawless to Included 3 as described below.

  • FL Flawless: no internal inclusions, but may have surface marks. Very rare.
  • VVS1-VVS2 Very Very Slightly Included (two grades). Minute inclusions very difficult to detect under 10x magnification by a trained gemmologist.
  • VS1-VS2 Very Slightly Included (two grades). Minute inclusions seen only with difficulty under 10x magnification.
  • SI1-SI2-SI3 Slightly Included (three grades). Minute inclusions more easily detected under 10x magnification.
  • I1-I2-I3 Included (three grades). Inclusions easily visible under 10x magnification AS WELL AS to the human eye.

While the presence of these inclusions do lower the clarity grade of a diamond, they can also be viewed as proof of a diamond’s identity. Grading certificates include what is known as a “plot”of a diamond’s inclusions — think of it as a “diamond fingerprint.” Since no two diamonds are exactly the same, you can identify your diamond by comparing its inclusions with the plot as provided by the grading certificate.

Furthermore, the type of inclusions to be found in a natural diamond is very different to those encountered in synthetic manmade diamonds. This helps the gemmologist to easily identify a natural diamond.

Which Clarity Grade Should I Choose?
While Flawless diamonds are the rarest, a diamond does not have to be flawless to be stunning.

Diamonds with VVS and VS grades are excellent choices for both value and appearance.

More affordable (and still a great choice) are those diamonds which gemmologists call “eye-clean” – diamonds with no inclusions visible to the naked eye. These diamonds are SI1 and SI2 and unless you look at it through a strong magnifying glass), you won’t see the inclusions. In large diamonds with a SI-3 clarity grade you may be able to see an inclusion with the naked eye.

I1-I-2-I3 Clarity. In a diamond with any of these grade the imperfections should be visible with the naked eye. Some buyers will buy such a diamond as they prefer to have a larger stone and do not mind seeing imperfections at close range.

4. Cut
The cut of a diamond should not be confused with its shape. The shape, or cutting style, is the outline of the stone as shown herewith. The round brilliant is the most popular shape as it normally sparkles more than other cuts. It is therefore also more expensive than fancy cuts.

Popular modern diamond shapes

Diamond cut is perhaps the most important of the four Cs. It is thus important to understand how the cut affects the properties and values of a diamond.

As shown in the images below, when a diamond is well-cut, light enters through the table and travels to the pavilion where it reflects from one side to the other before reflecting back out of the diamond through the table and to the observer’s eye. This light is the brilliance we mentioned, and it’s this flashing, fiery effect that makes diamonds so mesmerizing.

In a poorly cut diamond, the light that enters through the table reaches the facets and then ‘leaks’ out from the sides or bottom of the diamond rather than reflecting back to the eye. Less light reflected back to the eye means less brilliance.

Diamond Proportions
Most gemmologists agree that the best cut diamonds are those whose proportions fall within a certain range. The proportions, or parts, of a diamond are measured with a micrometer and expressed as a percentage of the diamond’s diameter. The depth percentage and the table percentage are two of the most important proportion parameters.

Because cut is so important, several cut grades have been developed to help consumers assess the cut of a particular diamond. In general, these grades are: Excellent – Very Good Good Fair Poor or Unusual.The difference between an Excellent and a Very Good Cut is difficult to see by the casual observer.

Which Grade of Cut Should I Buy?
Selecting the grade of cut is really a matter of preference and price. To make the best selection, you need to understand the various grades. Please note that the descriptions below are general guidelines.

Excellent Cut
This cut is intended to maximize brilliance. In the USA a brilliant cut with a small table (53-56%) is called an Ideal cut. Such a small table creates maximum dispersion or ‘fire’, ie. the colour flashes to be seen. Diamonds with excellent proportions are truly for the person who enjoys knowing that he has one of the finest things that money can buy. This category applies only to round diamonds.

Very Good Cut
In the case of round diamonds, those with Very Good proportions are the equal of any Excellent cut diamonds. They are intended to provide the best combination of brilliance and fire, as well as a slightly larger looking diamond. Like the Excellent Cut, these are also for the person who prefer to buy the best.

Good Cut
Diamonds that reflect much of the light that enters them. Their proportions fall outside of the preferred range because the cutter has chosen to create the largest possible, or a better clarity diamond, from the original rough crystal, Diamonds in this range offer an excellent cost-savings to customers who want to stay in a budget without sacrificing quality or beauty.

Fair, Poor and Unusual Cuts
A diamond graded as fair or poor reflects only a small proportion of the light that enters it. Typically these diamonds have been cut to maximize the carat weight over most other considerations. Unusual cuts are often Old Mine cut or old European cut diamonds with poor brilliance. (please note- some old cut diamonds exhibit very good brilliance and should not be called unusual). also add value to a diamond.

4. Certification
You can either buy a certified diamond, ie, one that has been graded and certified by an independent gemmological laboratory or a non-certified stone where the seller issues a valuation certificate. Because few jewellers are qualified gemmologists and some sellers may overstate the grade of their diamonds, an independently certified diamond, although costing somewhat more, provide peace of mind to the buyer.

Prins & Prins is proud to announce that all diamonds purchased comes with its own independant certificate, issued by either the European Gemmological Laboratory, or the Gemmological Institue of America.





5. Confidence
Paying many thousands of rand for a sparkling piece of carbon is a daunting exercise for most people. Buying a diamond from a reputable jeweller, or one that employs qualified gemmologists, ensures that you will receive professional advice in your search for a diamond. One can always get a bargain on the internet, but when it comes to comparing two diamonds, or returning or exchanging what you have bought, the internet experience becomes a nightmare.

Prins & Prins employs 3 qualified gemmologists and has been one of Cape Town’s leading diamond merchants for more than 30 years.

Enquire about the services and guarantees that your diamond supplier offers, for instance:

* Can you return what you have bought for a refund ?
* Can you upgrade your diamond in the future ?
* Will the jeweller buy back your diamond if you need to sell it in future?.
* What information, guarantees and valuation certificates accompanies your diamond?
* Can the diamond seller make your setting and set your stone without sending it to another shop?

The above and other services are offered by Prins & Prins. Feel free to contact us for any queries via our website, or come visit us at our offices in Cape Town. We look forward to welcoming you, and to let you experience our “Passion for Perfection”.