As a trained diamond grading professional DGA, Jemima has a comprehensive understanding of diamonds and diamond grading which is essential for the buying, selling and trading of diamond. Seen as one of the most valuable diamond qualifications worldwide it helps her to understand the properties of diamond, the factors affecting a diamond’s appearance and properties, learn about diamond grading, the 4Cs (carat weight, colour, clarity and cut) and the other factors that influence value, as well as how to identify and recognise imitations, synthetics and treatments.

At Hargreaves Stockholm our diamond jewellery with a carat weight of over .40ct is usually accompanied by a diamond certificate, also known as a diamond grading report or diamond quality document. This is a document produced by an objective 3rd party lab that describes the characteristics of your unique diamond.

Trained professionals put a diamond through thorough examination, whereby the diamond is evaluated, measured and scrutinised in a lab using industry tools such as microscopes and a jeweller’s loupe.

An example of a report you can expect to receive with our diamonds are those certified by GIA (Gemological Institute of America), often seen as the world’s most well-respected and renowned diamond grading entity. Founded in 1931, the GIA is the creator of the worldwide industry standard 4C’s of diamond quality. The 4C’s stand for Cut, Clarity, Colour and Carat; seen as the most important factors that determine the quality and price of a diamond.

1. Cut

The cut refers to the angles and proportions of a diamond, and also for its shape; for example, round, oval or pear. The cut is the first part of the certificate that you should look at because the sparkle and brilliance of a diamond depends more on its cut than any other factor. GIA uses a relative scale from “Excellent” to “Poor” to grade a diamond’s cut. A badly cut stone will leak light from underneath meaning your diamond will be less firey! At Hargreaves Stockholm, we only choose diamonds that have been graded ‘Excellent’.

2. Clarity

As diamonds are natural and formed deep within the earth under extreme heat and pressure, they often contain unique birthmarks. These can be either internal (inclusions) or external (blemishes). Diamond clarity refers to the absence of these inclusions and blemishes. With Classic Diamonds we look for no inclusions and blemishes.

GIA uses a grading system that assign a clarity mark that ranges from “Flawless” to diamonds with obvious inclusions. The GIA Clarity Scale contains 11 grades, with most diamonds falling into the VS (very slightly included) or SI (Slightly Included) categories. Diamonds without birthmarks are very rare, so rare that most jewellers have never seen one!

3. Colour

With Classic Diamonds, you are looking for a completely colourless stone as possible. GIA rates diamonds on a scale from D to Z.

D, E and F fall within the range of colourless with D being the highest grade. we choose diamonds which rank D to F. The scale continues with increasing presence of colour to the letter Z which is light yellow or brown.

4. Carat

Carat is a measurement of weight, not love. It is simply what the diamond weighs in metric carats which are a unit of measurement like kilos or pounds. Don’t confuse carat with karat (as in “14K gold”) which refers to gold purity rather than weight.

Keep it Safe!

As well as listing all of the physical attributes of your diamond, a diamond certificate is a valuable document which should be stored carefully as it can be used in cases of theft or loss to prove the diamond (or engagement ring) is your property.

To find out more information on how to read a diamond certificate, the GIA have created a handy overview video which you can watch here.