The Scottish Diamond Factory

The 4 Cs

The key to a perfect diamond purchase

You need to consider how important each of the 4 Cs is to you to help you find the perfect balance and the highest quality diamond for your budget.

Understanding the 4 Cs

The 4 Cs - colour, clarity, carat and cut - are key when it comes to choosing diamond jewellery, particularly if you are buying a diamond engagement ring. It is the interplay of these characteristics that determines the value, rarity and beauty of your diamond.

Just right for you

For example, you may decide on a diamond with a lower grade colour and less clarity in order to have a stone with a larger carat weight and a really good cut. Understanding the 4 Cs will help you find the diamond ring that's just right for you.

Diamond colour

 

Diamonds mostly appear colourless. However, many actually contain subtle shades of yellow or brown. The closer a diamond is to having no colour, the more valuable it becomes, because the light is free to play through it giving you a truly dazzling diamond. Diamonds can also be found in what are known as 'fancy' colours, including yellow, brown, pink and blue. These are extremely rare and valuable.

Diamond colour scale

At Ernest Jones, we use the GIA (Gemological Institute of America) scale of colour. On this scale, diamond colour is graded from D, which has the least colour, through the alphabet to Z, which has a light yellow colour. Truly colourless diamonds (D) are treasured for their rarity.

Subtle diamonds

The colour differences between diamonds are very subtle. It can be hard, for instance, to tell the difference between and E and F diamond and it can take years of experience and training to fully appreciate the subtleties. If you want to see the difference for yourself, however, ask a diamond specialist at your local Ernest Jones store to compare diamond engagement rings side by side.

Diamond clarity

 

Most diamonds contain inclusions - natural identifying characteristics such as minerals or fractures. These are known as nature's 'fingerprints' or 'birthmarks' and may look like tiny crystals, clouds or feathers. Most inclusions are invisible to the naked eye. The fewer inclusions in the diamond, the greater the clarity and the more valuable it is. Some inclusions can be hidden by a diamond's setting or mount and therefore have very little effect on the beauty of a diamond engagement ring.

The flow of light

When light enters a diamond, it is reflected in and refracted out. If anything disrupts this flow of light, some light can be lost and the diamond's brilliance may be diminished. The number, size and position of inclusions can affect this flow of light.

International grading scale

Inclusions are ranked on a scale of perfection called clarity. There are two main bodies that set these scales, the GIA (Gemological Institute of America) and the CIBJO (International Confederation Of Jewellery Silverware and Diamonds). At The Diamond Factory we use the International Grading Scale developed by CIBJO, which is the oldest representative organisation in the jewellery industry. The scales developed by both CIBJO and the GIA are based on the visibility of inclusions using a single lens magnifying glass called a loupe, which allows jewellers to see diamonds at 10x their actual size.

The CIBJO scale ranks diamonds from Loupe Clean through to P (Piqué - French for picked):

* Loupe Clean diamonds are flawless or internally flawless and very rare and valuable.

* Diamonds that have very, very slight inclusions, are graded VVS1-VVS2 and, even with a loupe, the inclusions can be difficult to see.

* Diamonds that are very slightly included are graded as VS1-VS2.

* Diamonds that are graded S1-S2 feature only slight inclusions which may or may not be visible to the naked eye.

* Any diamond that has inclusions that is visible to the naked eye, are P1-P3 although P1 will have fewer inclusions than P3.

Diamond carat

A diamond's carat is a measure of its weight, not its size. Larger carat weights are rare and valuable. However, two diamonds with the same carat weight can have very different values depending on their colour, clarity and cut.

What is a carat?

The word carat derives from ancient times, when gems were measured using the weight of a carob seed. One carat is equivalent to one fifth of a gram. It can also be divided into 100 'points.' If someone refers to a half carat diamond, this is the same as a 50 point or a 0.50 carat diamond. Similarly, a quarter carat diamond is equivalent to 25 point, or 0.25 carat.

If a piece of jewellery contains more than one diamond, for example a diamond cluster ring or a diamond three stone pendant, the stated carat weight reflects the total weight of all the stones together, rather than each individual diamond.

Is carat the same as size?

The carat weight of a diamond does not reflect its size. One diamond may look bigger than another but weigh less. A good cut and certain mounts can make a diamond appear larger than its actual carat weight, so it's worth taking your time to find the right diamond jewellery with a setting that optimises its beauty and brilliance.

Get the most from your diamond

Of all the 4 Cs, carat is often the key deciding when choosing a diamond engagement ring, pendant or earrings - especially if the jewellery you are buying features a diamond solitaire as its centrepiece. However, you should also consider that colour, clarity and cut are also important in determining a diamond's value and beauty.

Diamond cut

Diamond cut refers to the angles and proportions created when transforming a rough diamond into a polished diamond ready to be worn as jewellery. Cut is the only one of the 4 Cs that is not naturally created when the diamond is in the earth.

Diamonds are cut by skilled craftsmen to bring out the very best in a diamond. The skill lies not just in cutting the diamond itself, but also in the proportion, relationship and angles of each of the surfaces, known as facets. The craftsman polishes tiny facets into the rough diamond to create the table, crown, girdle, pavilion and culet.