Diamonds explained

GIA certificated diamonds available 

What you need to know about buying

a diamond.

‘Magic Sizes’

Carat weights known as ‘magic’ sizes signify a price increase once reached.

These are:

1/2ct – 0.50ct,

3/4ct – 0.75ct,

1ct – 1.00ct ,

1.5cts – 1.50ct,

2cts 2.00ct.

‘Under-sizes’ are diamonds that weigh just below a ‘magic’ size. In choosing a diamond which is slightly ‘under weight’ it is often possible to save up to 30% e.g. in choosing a diamond weight of 0.95cts, opposed to the magic size of 1ct. As carat is a measure of weight and not strictly size, it is possible that the two stones can appear to be the same ‘size’ when seen in direct comparison, though one is shy of a magic size as one diamond might spread more than another.

How to choose a diamond for an engagement ring:

Define your budget and spend as much as you are comfortable with. We can provide you with assistance to help maximise your budget.
To create an engagement ring it’s vital to consider finger size; remember that slender fingers can make small diamonds look bigger.
Consider lifestyle, will the ring be worn and seen on a regular basis?
Think about what sort of setting will hold the diamond, these will also determine the style of the engagement ring. Are you looking for something plain or something a little more extraordinary?
Find out what size diamond the recipient may be expecting.

The 4 C’s Carat, Clarity, Colour, Cut. 


Diamonds are weighed in carats with one carat weighing about the same as a paper clip, or 0.2 grams. Just as a pound is divided into 100 pennies, a carat is divided into 100 points which means that a diamond of 50 points weighs 0.50 carats. But two diamonds of equal weight can have very different values depending on their clarity, colour, and cut. Carat weight is the most intuitive of the 4Cs – you expect a larger diamond to be worth more.


Because they are created deep within the earth, most diamonds contain unique birthmarks called inclusions (internal) and blemishes (external). Diamonds without these clarity characteristics are rare – and rarity translates to higher cost when purchasing diamonds. Using the GIA Diamond Grading System, diamonds are given a clarity grade that ranges from Flawless to Included (I3).

I can supply certificated diamonds on request. The un-certificated stones I supply are also specifically chosen for colour G/H/I and clarity around VVS – SI.

You can substantially reduce the cost of a diamond if you see that the inclusion will be hidden behind the mounting and not affect the overall appearance of the stone.

You can get excellent value with diamonds which have ‘Slight Inclusions’ (grades SI1, SI2, SI3). You should consult with our diamond experts as to whether any of the inclusions can be visible to the naked eye. if so, they may be able to be hidden by the choice of mounting.

We only sell diamonds with a clarity grade of SI1 and higher.

What clarity grade is best?

FL (Flawless) is the best clarity grade and therefore the best to buy, it is also the most valuable grade of clarity.

The average person can’t tell the difference between FL and VS1 clarity diamonds, to ensure the diamond is free from visible inclusions (eye clean) you will need a VS1 or VS2 clarity grade.

Many people believe that all diamonds with SI clarity grade are eye clean, but this is far from true. There can be visible differences between two diamonds with the same SI clarity grade, and this will depend on the number, type, size, and location of the inclusions.

Types of clarity flaw

There are 2 types of flaw:

Inclusions are flaws within the stone itself such as air bubbles, cracks, and non-diamond minerals; blemishes are surface flaws such as scratches, and pits.

For the purposes of grading diamonds, all flaws are called ‘inclusions’. Diamonds are graded for clarity under 10 to 30 times magnification. Grades range from ‘Flawless’ (completely free of blemishes and inclusions), to ‘Included 3’ (diamonds which possess large, heavy blemishes and inclusions that are visible to the naked eye).

diamond clarity scale

Flawless Perfect inside and out. No inclusions or blemishes visible to a trained jeweller, even under high magnification.

Internally Flawless Absolutely no inclusions inside of the diamond. Only very slight surface blemishes, most often from when the stone was cut,visible only to a trained jeweller under 10x magnification.

VVS 1 or 2:
Very Very Slight inclusions VVS1 takes a trained jeweller 10x magnification to detect the smallest inclusion which are extremely difficult to see. The same with VVS2 but only slightly easier to find. Not visible to the naked eye.

VS 1 or 2:
Very Slight inclusions VS1 the inclusions are still invisible to the naked eye and are still somewhat difficult to find under 10x magnification. VS2 the inclusions are invisible to the naked eye but are now easy to see with magnification.

SI 1:
Slightly Included,Inclusions can now be seen with the naked eye but they are very tiny.

SI 2:
Slightly Included,Inclusions are small, but now easy to see with the naked eye.

I1 or 2:
Included, Numerous inclusions through a large amount of the diamond, most of which are quite obvious.

Included, Very included. The inclusions are large and very obvious. The number of inclusions could cause the diamond to be structurally weaker.


Most diamonds found in jewellery stores run from colourless to near-colourless with slight hints of yellow or brown. The only exceptions are the fancy-colour diamonds that lie outside of this range.

The whiter and more colourless a diamond is, the greater its value.

D-F – Colourless – naturally the most valuable and desirable because of their rarity.
G-I – Virtually no discernible colour visible to the untrained eye.
J-M – Very faint hint of yellow will be apparent however, this can be minimised by selecting the right mount.
K-Z – Visible colour tint.




It seems miraculous that the traditional 58 tiny facets in a round cut diamond, each precisely cut and sharply defined, may be only two millimeters in diameter. But without this precision, a diamond wouldn’t be near as beautiful as it is. Without a doubt, the allure of a particular diamond depends more on cut than anything else.

What makes a well–cut diamond?

A well-cut diamond will have angles which allow light to reflect back into the eye of the beholder.

When a diamond is well cut, and viewed face-on, light enters through the top of the stone where it reflects from one side to the other before bouncing back out of the diamond to be seen by the viewer’s eye. This light is called the ‘brilliance’.

In a poorly cut diamond, light entering the diamond ‘leaks’ out from the sides or bottom rather than reflecting back to the eye.

The less light reflected back into the eye, the less brilliance a diamond emit.

When searching for diamonds consumers should be aware of the following parameters about the numerous so called diamond certificates available.

Having industry insight, knowledge and experience, we can authenticate the following detail.

GIA – Is the foremost authority in diamond grading and the industry leader. Our experience shows that if you wish to purchase any diamond over £5000 and up you should ideally be looking for a GIA certified diamond. Most expensive diamonds sold at auction houses like Christies and Sotheby’s are offered ONLY with this certificate. This is a fair barometer of its authority in gemmological terms.

HRD and IGI – Are both based in Antwerp. In my opinion, a diamond with this certificate can be used for purchased between £2,000-£20,000.

AGS – A fairly well recognised lab predominant in the USA but hardly available in the UK.

Gubelin, GRS and SSEF – based in Switzerland, are the main authority on grading important coloured gemstones and natural pearls.

In essence, if possible, look firstly for GIA, then HRD or IGI certified diamonds. Avoid purchase of any other certified or non-certified solitaire (over one carat) diamond if you can help it, especially if spending a substantial amount of money which you can ill afford to loose.

Besides the above three, there are 100’s of worldwide gem labs offering diamonds with their own “independent” certification. Predominant in the UK are the AGI, EGL, GIE, IDL, and IGL (with new ones introduced all the time) and some retailers offer their own so called certificates.

Generally, these labs are NOT recognised by trade experts and prices can differ to the extent of double the actual value. For example, a 1ct GIA certified F colour VS2 clarity diamond may be selling at a retailer for £8000 and a 1ct FVS2 diamond could be offered on another “so called” certificate for £4000. Actually, this diamond would be of a H-J colour and SI1 or lower clarity on the GIA grading scale.

To the untrained consumer eye, they may look similar until the time comes to sell the diamond, if need be. In our opinion, if your budget is £4000, buy a 1ct H colour SI1 diamond certified by the GIA rather than the same diamond shown as FVS2 1ct by a generic lab for £4000.

A properly certified diamond (by the GIA) should either go up in value over a very long period of time or remain relatively stable, whereas other diamonds certified by generic labs may generally loose up to 70% of its value. An “independent” certificate does not mean anything unless it truly shows the colour and clarity of the diamond offered on a GIA grading scale. We strongly recommend NOT to purchase solitaire diamonds certified by other labs except for GIA, HRD or IGI. For such an important high value purchase.

Round Brilliant Diamond

Princess Cut Diamond

Emerald Cut Diamond

Oval Cut Diamond

Marquise Shaped Diamond

Pear Shaped Diamond

Radiant Cut Diamond

Cushion Shaped Diamond

Asscher Cut Diamond

Heart Shaped Diamond

Avoid conflict diamonds

If you are a conscious shopper, you will ask more questions when shopping for diamonds that just about the details of the stone. You should enquire if the stones you are admiring with the possibility of purchasing are non-conflict diamonds. The answer you receive should satisfy your mind that these diamonds have not come from a country where the sale of diamonds is used to cause bloodshed and terror for others.

Non-conflict diamonds do not look any different from other diamonds so there is no way you can identify them by looks alone. Conflict diamonds, also called blood diamonds, should be a cause for concern because they come from countries in Africa where they are used to provide financing for wars and military action against innocent people. In short rest assured that all the diamonds used in the manufacturing process I supply come from non-conflict sources.