Your Diamond Education
Diamonds may be a girl’s best friend, but arming yourself with a complete knowledge of the characteristics of diamonds will be your best friend as you begin the hunt for the diamond ring.
By reading this guide completely, taking notes as necessary and highlighting important points, you will be in a position to save potentially hundreds, if not thousands, of pounds of your hard earned money through careful diamond selection, finding a trusted diamond merchant and negotiating for a great deal.
The 4 Cs and 3 Others
Perhaps the most well known characteristics of diamonds (aside from their toughness) are the “4Cs”. These are:
I also believe that there are three other Cs which could be added.
- Certification (from independent gemological laboratory)
- Choice (of merchant)
- Conflict (diamonds)
The following sections will give a thorough explanation of each of the Cs.
The cut of a diamond refers to the way in which it is angled and proportioned.
The cut is arguably the most important of the 4Cs because the intensity of the sparkle and brilliance of the diamond is mostly due to the quality of the cut. The different angles and lengths contribute to how much of the light that enters the diamond is reflected internally and then back out again. This is the diamond’s “sparkle”.
It is also one of the most difficult of the Cs to rate. One particular cut may appeal to one person but not to another. Before discussing the specifics of the cut it would help if you were familiar with the names of the major measurements of a diamond.
When you visit a jeweller/merchant they will use these names when describing a particular diamond's proportions to you.
When a diamond is graded by an independent laboratory all of the proportions are taken into account to
arrive at a grading of the proportions (cut). The diamond grading certificate will state what standard the proportions (cut) are. For example the GIA grading will state that the proportions are either:
- Very Good
There are precise mathematical formulas for determining the cut of a diamond that gives the optimum amount of sparkle.
One of these types of cut is called the “Ideal Cut”.
With regards to the shape of the diamond, the round cut gives the most intense sparkle because it suffers from the least amount of "leakage”. Leakage is the amount of light that is reflected out of the sides of the diamond rather than the top.
Each of the flat surfaces of the diamond is called a facet.
A diamond’s facets will either let light pass through or reflect the light. The angle that the light hits the facet determines whether the light is reflected or passes through.
The girdle is the circumference of the diamond that marks out its diameter. The girdle should be an even depth right around the entire diamond.
Ideally the girdle should be somewhere between thin-medium to slightly thick. If the girdle is too thin then it may be prone to chipping. If the girdle is too thick then the diamond carries its weight around its middle rather than being a wider diameter and you get a diamond that looks smaller than what it should for the price you pay. The culet is the point of the diamond.
Assessing the Quality of the Cut
Initially, assessing the quality of the cut will be difficult for you to do. Cut is one of the most subjective of the 4Cs to assess because one individual will assess sparkle intensity differently to another.
As you have done with the other 3 Cs, calibrate your Cut radar by asking your jeweller to compare an Ideal Cut diamond with a poorly cut diamond. You should easily be able to notice the more intense sparkle that the Ideal Cut exhibits.
Then, have your jeweller bring out progressively better cuts of diamond to compare to the Ideal Cut diamond, and note the point where you can no longer make a distinction between the difference in sparkle.
A second element of the diamond cut is the shape of the diamond. The most common of these for an engagement ring is the round shape.
Some shapes popularity increases as trends change. If you are looking for the most sparkle from your diamond then stick with the round shape diamond as the geometry of it means that there is less leakage compared to the other types of diamond shape.
HCA – Scientifically Evaluating a Round Diamond’s Sparkle
An Australian master jeweller by the name of Garry Holloway devised the Holloway Cut Adviser (HCA) as a scientific means of determining the amount of sparkle that a round diamond exhibits, based on the proportions of that diamond.
Holloway’s test uses four factors to describe the quality of the diamond’s visual appearance. These are brilliance (light return), fire, scintillation and spread. These are described below.
Brilliance (light return)
Brilliance is the perception of a diamond’s brightness. A bright diamond will return a lot of light back up to an observer.
Fire is a measure of the dispersion of the light that is returned back to a diamond’s observer. A diamond with good fire appears to have a lot of flashes of rainbow colours. This aspect of the diamond’s appearance is best viewed with less light, otherwise the fire flashes get swamped by the sparkle of the diamond.
Scintillation is the intense sparkles that occur when a diamond is moved about. Ideally there are many areas of scintillation across the face of a diamond with few dull patches.
Spread is a measure of the apparent size of a diamond and should be an important factor in your buying decision. Obviously you want to be able to purchase the largest diamond you can with the money you have available, while also factoring in quality for the other 3 Cs. Whilst size doesn’t play a large part in the beauty of a diamond, it certainly contributes to the desirability of that diamond.
The depth percentage value is used to give a range for a good diamond spread. Using Figure 8, if you divide the depth of the diamond by the diameter of the diamond you should get a value that is somewhere between 56% and 65%.
As with the other Cs, proof of a diamonds’ cut can only be verified with an authentic laboratory certificate.
The laboratory certificate for the diamond will give values for proportions of the cut such as:
- Shape e.g. brilliant
- Measurements, i.e. diameter and depth
- Assessment of proportions, e.g. very good
- Depth or % of girdle
- Type of culet (the point of the diamond)
- Table Width
- Crown Height
- Pavilion Depth
Some of these proportions can be used in a calculation that determines the values for the:
The Ideal-Scope is another tool developed by Holloway. It helps assess the standard of the cut of a diamond by measuring the sparkle (brilliance). It is a small eyepiece which has a special type of lense in it. You look through the eyepiece at the diamond you are assessing and a certain array of patterned colours is reflected based on the standard of the diamond cut.
It is a fairly advanced diamond purchasing tool, but Holloway claims that with only a little practise a layperson can eliminate 80% of all round diamonds as being an inferior cut using the tool.
For more information please visit www.ideal-scope.com
Tips on Diamond Cut
When evaluating a diamond’s cut:
- Use the laboratory certificate measurements to determine that the diamond has an optimum spread of between 56% to 65%.
- Start with an ideal cut and a poor cut so you are able to gauge the standard of a diamond’s sparkle. Then get progressively better diamond cuts to compare against the Ideal Cut until you can’t tell the difference.
- Make sure the girdle isn’t too thick as the diamond will be hiding its weight in the girdle area and won’t look as big. Conversely the girdle shouldn’t be too thin as it will be more prone to chipping.
The clarity of a diamond refers to the amount of visible flaws in the diamond. The fewer the visible flaws, the more expensive the diamond.
|Less Flaws = More Expensive|
Flaws that are visible on the surface of the diamond are called blemishes. Flaws that are visible inside the diamond are called inclusions.
NB: Stones are what diamonds are called within the diamond trade.
A loupe is a small magnifying glass that is held up to the eye.
There are many terms used to describe the types of flaws that can occur in diamonds. Some of common ones are:
A crystal is any mineral crystal that is enclosed by the diamond. They can also occur on the surface of a diamond. They can be any size, shape or colour but the most common ones appear like a small clear bubble to the naked eye. They are sometimes referred to as "carbons”, “carbon spots” or “bubbles”.
A feather is any type of break or fracture in a diamond. They often have a feather-like appearance, hence the name. A heavy knock to the diamond can make them larger.
A pinpoint is a type of crystal that is very small and cannot be seen by the naked eye, only with a 10x or greater magnification.
A cloud is a very tightly packed group of pinpoints that looks like a cloud under 10x magnification.
An abrasion is a series of very small nicks or chips on the surface of a diamond, usually along a facet line. These are caused by wear and tear when diamonds are not stored carefully with other diamonds (as only diamond can scratch diamond).
For a more detailed coverage of the various types of flaws, including photos, please visit:
Each time you view a diamond, have the jeweller show you the flaw diagram on the laboratory certificate and ask him to point out these flaws on the diamond itself. If the diamond has good clarity it may be difficult to see these flaws but persevere, once you have seen the most common types of flaw once, it will become easier to find them on other diamonds.
Tips on Diamond Clarity
When assessing a diamond’s clarity:
- ALWAYS use at least a 10x magnification eyepiece (known as a loupe in the industry). If you use a lower magnification you may not pick up all of the important flaws in the diamond.
- Always view the diamond un-mounted. If the diamond is already mounted in a ring, the mounting claws and the mounting itself may obscure any flaws.
- Always buy a diamond with an independent laboratory certificate. The flaw diagram on the laboratory certificate will be marked with the locations of the flaws that were identified when the grading was performed. The flaws are a great distinguishing feature of each individual diamond. They can be a good means of assuring yourself that the diamond you are viewing is actually the same diamond that is graded on the laboratory certificate, and that a "switch” of diamonds hasn’t taken place.
The colour of a diamond refers to the amount of “yellowness” that the diamond has. While typically you might think of diamonds as being colourless, in fact, most have a yellow hue to them (due to nitrogen contamination). If the other 3 Cs are held equal, the more colourless the diamond, the more expensive that diamond is.
|Less Yellow = More Expensive|
However, very intensely yellow diamonds are highly prized and can be very expensive. These are known as Fancy Yellow diamonds.
Colour is graded on sliding scales. The GIA (Gemological Institute of America) scale, ranging from D to Z, is the most common colour scale used in the UK. Some of the other gemological laboratories have a different scale for diamond colour.
Because of the gradual increase in colour up the scale, it is very difficult for the untrained eye to tell the difference between one grade and the next grade. For example, telling the difference between an “F” colour diamond and a “G” colour diamond is difficult. However, it is much easier to tell the difference between a “D” grade diamond and an “I” grade diamond.
“D” colour diamonds are very rare and subsequently are very highly priced relative to the other colour grades.
So you now know, if you decide that you wish to buy a near colourless diamond then you pay proportionally more for a “D” grade than you do for an “E” grade.
You might be wondering how a diamond is actually assigned a colour grade. There are two primary methods:
- Using a set of reference diamonds. These are a set of diamonds that have already been graded for colour by one of the gemmological institutes. They act as a baseline for determining the colour of other diamonds that they are compared to. Once the diamond has been graded, this grade is entered onto its laboratory certification and will not need to be graded for colour again.
- A Colorimeter. This is a device which beams a ray of light through the top of the diamond. The beam passes through the diamond and then through various light filters. A receptor analyses the beam and measures the absorption of the colours. The analyser determines the colour of the diamond according to the degree of absorption of the other colours of light.
Fluorescence is a factor that partially affects the colour of a diamond that you may not even hear mentioned by any jeweller you consult. Fluorescence is the glow that is produced when a diamond is exposed to ultraviolet (UV) light. It is due to the diamond containing tiny amounts of the element Boron. The most common glow colour is blue, although other colours are also possible.
There is ongoing debate about whether fluorescence actually improves or detracts from a diamonds appearance. Whatever the case, most consumers try to avoid diamonds with fluorescence and will certainly not pay a premium for a diamond with fluorescence.
Tips on Diamond Colour
When assessing a diamond’s colour there are a few rules of thumb you should follow:
- You must look through the side of the diamond to see the true colour, not the top or bottom.
- The diamond should be viewed against a plain, preferably white background (a black or dark background will make a diamond look more white than it actually is).
- Start by “getting your eye in” by comparing diamonds with several grades of colour between them, for example, a “D” coloured diamond with a “J” coloured diamond (keep the other 3Cs constant.) The difference should be quite noticeable. Move onto comparing, say, an “E” with a “H”. These should be more difficult to tell apart. Finally, compare two stones of only one colour grade difference, such as an “F” compared with a “G”.
- The diamond must be un-mounted, that is, not already set into a ring. If it is already mounted you will find it very difficult to get a clear view of the diamond and thus a true indication of its colour.
Always purchase diamonds that have been graded by one of the independent gemological institutes and have an authentic laboratory certificate accompanying the diamond.
- Make sure the diamond is being viewed under lighting that simulates natural light conditions as closely as possible. Some jewellers use bright halogen lamps which give an unnaturally intense sparkle to a diamond. The diamond will then look much duller when viewed in natural light.
- A jeweller will generally “round up” the colour of a diamond in his/her favour, for example, if a diamond colour grade looks like it is somewhere between an “F” and a “G”, the jeweller will round it to “F”, as this would command a higher price. To avoid this, always make sure the diamond has a laboratory certification, from which you can then confirm a diamond’s officially graded colour.
The carat of a diamond is actually a measure of the weight of the loose diamond.
1 carat = 200 milligrams
A carat is divided into 100 points.
So, as an example, 1 carat and 21 points is written 1.21 carats and would equal 1.21 x 200 milligrams = 242 milligrams. The larger the carat of the diamond, the more expensive that diamond is, with the other three Cs being equal.
|More Carat = More Expensive|
Remember, the carat of a diamond is the weight of the stone, not the size of the stone. However, there is an obvious relationship between carat and size for the common types of shapes for diamond.
As larger diamonds are much rarer than smaller diamonds the increase in price is non-linear. Also, as the diamond carat reaches the whole numbers such as 1.0 or 2.0 carats, the price for the diamond increases at a faster rate approaching the whole carat weights. This is because wholesale diamonds tend to be priced in
whole carats, which leads to the larger relative jump in price around these numbers and there is also an “exclusivity“ factor surrounding the whole carat numbers.
The size of the diamond is undoubtedly the most noticeable of the diamond’s characteristics. While it will be tempting to go for the biggest diamond available for your budget, you should bear in mind that despite what they say, size isn’t everything. The quality of a diamond is dependant on the other 3 Cs also. Educating your
girlfriend/fiancée about this is another part of your job.
The diamond carat is the C that is most easily able to be measured, as it is simply the weight of the diamond. This makes the carat an ideal C to use as a benchmark when evaluating diamonds. Hold the
carat as a constant for different diamonds and then compare how differences in the other 3 Cs affect the cost of those diamonds.
Tips on Diamond Carat
When evaluating a diamond’s carat:
- Make sure the jeweller is using calibrated electronic jewellery scales to weigh the diamonds he/she is showing you. Check this measured carat against the carat that is on the laboratory certificate.
- Ask the jeweller what his/her opinion of the cut of the diamond is. A poorly cut diamond may hold its weight
around its middle and therefore look smaller in diameter than what it should. In effect you will be paying more for a diamond that doesn’t look as big.
The Other 3 Cs
Now that we have covered the traditional 4 Cs, you should be well positioned to talk knowledgably about diamonds with the various retailers and merchants that you will visit while searching for that perfect diamond.
However, in my opinion, there are also 3 other Cs to consider.
Many diamonds have been graded by an independent gemological laboratory. The report produced from the grading process is called an independent diamond grading certificate or independent diamond grading report.
Each report details certain characteristics of the diamond that has been graded.
There are 5 main gemological institutes that handle the
independent grading of diamonds.
GIA is the Gemological Institute of America. This is recognised as one of the leading grading labs in the world and is a non-profit organisation. The world headquarters are located in California, USA.
Their website has some very good interactive diamond education tutorials.
AGS is the American Gem Society. It is half investor-owned and half jeweller-association owned. They have the reputation of grading the very best diamonds and hence you will pay more for an AGS certified diamond.
HRD is the Antwerp World Diamond Centre located in Antwerp, Belgium. It is a non-profit organisation. One of the departments is HRD Certificates. As a European-based lab, HRD certificates do not get much mention on the more prevalent US-based diamond informational sites. However, they do have a very good reputation in Europe itself, and are essentially the European equivalent of GIA. This laboratory was the first worldwide to gain accreditation itself for the quality standards of EN 45001, ISO/IEC Guide 25 and ISO 9002.
8 out of 10 rough diamonds pass through Antwerp, and 1 out of every 2 cut diamonds.
EGL is the European Gemological Laboratory. This is a network of iinstitutes located in South Africa, India, Belgium, the UK, Israel, Turkey, Korea, and France.
IGI is the International Gemological Institute. This is one of the smaller laboratories.
Tips on Diamond Certification
- In my opinion, it is ESSENTIAL to purchase a diamond with a grading certificate from a reputable laboratory. This is one of the few assurances you have that the diamond you are buying is authentic.
Category of Diamond Retailer
The next C is the choice of category of diamond retailer that you purchase the diamond from.
The main categories of merchant are:
- International Jewellery Brand with UK stores(s)
- National Jewellery Chain
- Independent High Street Retailer
- Online Diamond Merchant
- Independent Diamond Merchant
- Diamond Jewellery Designer
Each of the different types has advantages and disadvantages.
International Luxury Brand with UK store(s)
These are the world’s most exclusive luxury jewellery brands that command a premium price. Customers are then able to say that they own a branded piece.
Examples of these brands are:
- Tiffany’s www.tiffany.com/uk
- De Beers www.debeers.com
- Bulgari www.bulgari.com
- Cartier www.cartier.com
These brands employ the very best designers and use excellent quality diamonds to create spectacular rings. However typically these brands command exorbitant prices. They have been built around the concept of exclusivity and are aimed squarely at the upper end of the market.
While you can narrow down the search to a particular setting and size of diamond by visiting a national jewellery chain store, the famous brands offer their own particular designs of settings that national chains will not carry. If your fiancée/girlfriend wants a special design for her ring then famous brand stores could be the place to find it. However once she has found the design that she likes you can get the design replicated by a craftsman and pay far less doing it this way. Be careful about infringing copyright laws if you do decide to go down this route.
- Absolutely beautiful jewellery, which can expand the mind as to what is possible for a diamond engagement ring.
- Staff tend to be highly trained and willing to spend more time educating prospects who walk in.
- Jewellery bought from these luxury brands is usually very exclusive and hence likely to not be found on many other fiancées fingers.
- As these are premium brands, you can be fairly certain that you are not going to be scammed (although always buy a diamond ring that has an independent laboratory report).
- These stores are unlikely to hold loose diamonds, meaning that most will already be set. If you are thinking of purchasing one of these branded pieces this will limit your flexibility on the type of setting if you find a particular diamond you like, and vice versa.
- Potentially difficult to get to as most only have stores in London.
- Extremely expensive due to the fact that they are a luxury brand and charge a hefty premium.
- Unless you are smartly attired don’t expect a great deal of attention from sales assistants. These stores often get “rubber-neckers” and tourists who have no intention of purchasing, and subsequently a sales assistant will try to quickly qualify whether you are really in the market for a piece using whatever signals are available.
National Jewellery Chain
These are the familiar national companies that advertise extensively in national media and have a store in most cities and main towns.
These stores are fairy common on the High Streets of most towns and cities. This makes them an excellent first stop when venturing out on your first browsing mission.
Staff will be moderately trained but you will have at least as much knowledge as them (if not more) after you have read this guide. Remember that these are sales assistants and will attempt to sell you a piece of their jewellery. Be sure to read all of this guide as it details persuasion techniques that these assistants are likely to use on you, and the methods to counter their tactics.
These stores will also use fairly standard High Street “Sale Ends Soon” type promotions and it is important not to be suckered into a purchase because of one of these seemingly “great deal going quickly” campaigns.
There are large profit margins that get added at each stage of the diamond supply chain, and one of your aims is to either avoid or to whittle down as many of these profit margins as possible.
- Fairly common in most towns so a good first stop in your diamond viewing adventures.
- Should have access to a fairly large range of different rings so you can get a good idea of what your girlfriend/fiancée likes by visiting a few of these stores.
- Nationally recognised brands you can trust not to sell you a fake diamond.
- Staff only moderately trained and you probably won’t learn anything new from them.
- As they have set prices on most pieces it is much harder to negotiate on their jewellery.
- Like the famous brand companies, most of the diamonds will already be mounted in a setting. This limits your flexibility around customising settings.
- They cater for the mass market so they are unlikely to have many creative designs.
Independent High Street Retailer
These tend to be the family-owned stores that may have been retailing for many years in your local town or city.
Their main areas of strength are that they offer easily-trusted, personalised service which they use to survive competitively next to the national jewellery chain stores. They will probably have strong links with local jewellery makers so can be a good option for having a customised setting produced.
- Should be fairly close to where you live so easy to get to. A good place to start ring browsing.
- Stay in business using personalised service, gaining high levels of trust and getting repeat business so you should be well treated in these stores.
- Probably not as price-competitive as the national chain stores.
- May not have breadth of range of rings that national chain stores do.
Online Diamond Merchant
Many national chain jewellers and independent high street retailers have websites that their jewellery can be purchased from. There are also online retailers who have either very limited or no “bricks-n-mortar” stores at all.
The cost savings of buying through the internet can be considerable. An online merchant can avoid the high overheads of maintaining a shop in a High Street location and does not have to carry as much stock as a traditional jeweller. Adding to this is the fact that most online merchants actually reduce their profit margins so as to be an even more attractive proposition over the bricks-n-mortar retailers. This price reduction can be anywhere between 30% and 50%!
- An excellent source of high-quality information about diamonds.
- Very price-competitive.
- Usually have many excellent tools, such as price comparators and build-your-own-ring functions.
- If you pay by credit card you are covered for fraud by your credit card issuer.
- Unable to see and touch the ring before it is delivered.
- Difficult to associate a salesperson with the purchase if anything is to go wrong with the purchase.
- Don’t get personalised service (could be a plus if you want to avoid any hard-sell type tactics).
Independent Diamond Merchant
An independent diamond merchant is an individual or company that buys diamonds directly from a diamond exchange. They may also buy or trade diamonds with other diamond merchants. A diamond merchant may also be called a diamond broker or a diamond trader.
Typically, independent diamond merchants will only have a very small shop or simply an office, and deal on a one-on-one basis with their customers.
These two factors explain the large cost savings that can be made by purchasing from a diamond merchant. They are closer to the start of the supply chain and so a manufacturer and retailer store haven’t added their margin into the price equation, and they do not need to hold large amounts of diamond stock, or employ many staff, nor have the other overheads of running a retail store. Like the online diamond retailer price reductions of 30% to 50% can be achieved compared to buying from the High Street!
Typically, the diamond merchant will source the loose diamond for you and he/she will have that diamond set into a ring by a goldsmith that they have a supplier relationship with.
They could at your instruction, work with a designer to merge your perfect diamond with the perfect setting. This will of course be more expensive than using a stock setting provided by a goldsmith.
- Diamond merchants usually have expert knowledge about diamonds.
- Very personalised service – often you deal directly with the merchant.
- Very price competitive, as they cut out parts of the supply chain and don’t have overheads of running a store(s).
- Don’t necessarily have stock to hand so go there already having asked them to source a selection of stones for you.
Diamond Jewellery Designer
A jewellery designer will generally not source the diamond for you; they will leave that up to an independent diamond merchant. What they will do is bring to fruition the diamond engagement ring in your mind's eye.
- Generally unique pieces, so no one else will have a ring like it.
- No matter how garish or unusual your design, he/she will produce what you want.
- More expensive as the exclusivity carries a price.
- You will need to source the diamond separately before getting it set by the designer.
A good price, good service, no pressure to buy, and trust in the retailer are all factors which play a part in the purchasing decision and it is usually these factors that get mentioned when someone gives you a word-of-mouth recommendation.
Because we are in a time when the buyer is spoiled for choice for retailers who can fulfil his/her needs, a friend’s opinion can be a real time-saver.
- Cuts out all the legwork of having to vet a merchant/retailer for trust, experience, authenticity.
- Blindly following advice without doing any research will mean you don’t minimise your spend/maximise your diamond. Find out how much research your friend actually did first.
In relation to diamond trading, conflict diamond (also called a converted diamond, blood diamond, hot diamond, or war diamond) refers to a diamond mined in a war zone and sold to finance an insurgency, invading army's war efforts, or a warlord's activity, usually in Africa where around two-thirds of the world's diamonds are extracted. Conflict diamonds are estimated to make up about 4% of the world’s diamond production. Three countries where many conflict diamonds are sourced from are Sierra Leone, the Congo and Angola, all in diamond-rich West and Central Africa.
If you purchase a conflict diamond then you are perpetuating these terrible actions and the vicious cycle.
The best way to avoid purchasing a conflict diamond is by getting proof from your shortlisted retailers that their diamonds are conflict free and were traded under the auspices of the Kimberley Process. The Kimberley Process Certification Scheme (KPCS) is the process designed to certify the origin of rough diamonds from sources which are free of conflict funded by diamond production.