How to choose a diamond

Diamonds are almost a household name. Apart from being a universal symbol for wealth, luxury, and class, they have performed extraordinarily as assets, not devaluating in decades.

Diamonds have never been seen as a tangible commodity that investors could hold as a long-term asset. They have always had value, but there was no clear way to determine the market value of a diamond.

In the 1950s, this all changed when the GIA (Gemological Institute of America) cut-grading system was introduced. The GIA became the diamond industry’s benchmark by which diamonds would be certified.

This standard introduced the concept of the 4Cs, which are the essentials you need to know when you buy a diamond:

Clarity, Colour, Carat weight, and Cut.


The diamond’s weight, that reflects its apparent size.

Each carat of a diamond represents 200 milligrams, and can be subdivided into 100 ‘points’. This allows diamonds to be measured up to a single percent (for example, a ‘fifty-two pointer’ is 0.52 carats.)

Carats are only the start of measuring a diamond’s value, but they certainly help: All things being equal, a bigger diamond is always more valuable than a smaller one!

0.50 ct0.50 ct 0.75 ct 0.75 ct 1.00 ct 1.00 ct 2.00 ct2.00 ct 5.00 ct5.00 ct


The purity (or lack) of a diamond’s colour.
“Stained” diamonds, therefore, have less value than those with no hue. A perfect diamond is like a drop of water: Colorless.

Diamond color distinctions are only visible by a trained expert, but can have great repercussions in the diamond’s perceived quality and price.

Colourless Near Colourless Faint Yellow Very Light Yellow Light Yellow
D, E, F G, H, I, J K, L, M N, O, P, Q, R S, T, U, V, W, X, Y, Z


A diamond’s cut grade is about how well a diamond’s facets interact with light, giving it fire, sparkle and brilliance. Some designers and brands have intellectual property rights over certain cuts, which makes them rarer and more valuable.

A diamond’s cut is its most complex, technically unique feature. Despite the diamond’s shape or artistic design (oval, round, heart, pear, marquise, etc), its interaction with light is what ultimately increases its beauty —and therefore value.

Excellent Very Good Good Fair poor
Refracts and reflects light perfectly Increased darkness in main pavilion Shallow pavilion angle Lack of contrast giving a flat dark look Thick girdle gives an extremly dark and flat


The clearness of the inside of the diamond, which demonstrates its resistance to heat. A perfect diamond, like a drop of water, has no impurities or blemishes on its inside.

Although ‘perfect’ diamonds are almost impossible to find, the Clarity of a diamond can be determined by the number, size, relief, nature, and position of these impurities, as well as their impact in the general beauty of the piece.

No inclusions No inclusions Very light inclusions. Takes even a skilled person time to spot them Minor inclusions. Can be seen under microscope Inclusions can be seen under microscope Inclusions can be seen easily