To grade ‘whiteness’ (or colourlessness), a jewellery colour scale is used that starts at D (colourless) and continues down through the alphabet to stones with traces of light yellow or brown colouring. The first three grades of D, E and F are often called the collection colour and are of course the most valuable. Truly colourless diamonds are an absolute treat for the eyes and make the most beautiful diamond jewellery imaginable. Diamonds graded from G to I are graded as slightly less than colourless but will appear virtually colourless to anyone with an untrained eye.

Normally, colour being present in a diamond makes it less valuable, but some diamonds come out of the ground in incredibly vivid colours. The diamond industry’s term for these diamonds are “fancy” colours and they can be any colour from pink to green or even bright yellow. These diamonds are incredibly rare and valuable, and are a true prize of diamond jewellery.

Cut

Contrary to popular belief, the ‘cut’ of a diamond refers to its reflective qualities rather than its shape. The brilliance of a diamond depends heavily on its cut, so the angles and finish of any diamond are the key factors in its ability to negotiate light. A good cut gives a diamond that magical brightness that seems to emanate from deep inside itself.

Clarity

Most diamonds contain some minor imperfections that have occurred during their formation. Industry experts call these imperfections ‘inclusions’.  The number, size and visibility of these inclusions are what determine the overall clarity of a diamond. Diamonds rings which are free of inclusions are fantastically brilliant and so are very highly sought after.

Colour

A colourless diamond allows more light to pass through it than a coloured diamond and so creates a greater sparkle. Completely colourless diamonds are rare so the more “white” a diamond’s colour is, the greater its value.

Carat Weight

A carat is the unit of weight by which diamond jewellery is measured, with one carat being equal to 0.2 grams (200 milligrams). Larger diamonds have a greater value per carat as they are discovered much less frequently than smaller diamonds.