Diamonds are not all created equal, so it's important to do your research before you commit to your purchase.
To understand a diamond's value, you must assess the diamond's 4C's- Cut, Clarity, Colour and Carat Weight.
Cut
The way a diamond is cut is the most important of the 4C's. Cut refers to the angles and proportions of a diamond, which determines the diamonds beauty, brightness, sparkle and scintillation.
A perfectly cut diamond can sparkle 3-4 times more than the average diamond, this is because every facet that is cut correctly will reflect light out the top of the diamond, creating maximum sparkle.
Carat
A Diamond's weight is measured in Carats and points. The larger the diamond, the more rare it is, so all other factors being equal, a single 1-carat stone is worth more than four quarter carat stones together.
100 points equals 1 carat (1.00ct). A diamond weighing one quarter of a carat, can also be referred to as 25 points or 0.25ct.
Colour
Diamonds come in a variety of colours, ranging from colourless, clear diamonds to those that have a yellow or brown tint. The less colour, the higher the grade and the more desirable & valuable they are.
A diamonds colour is determined on a scale from 'D' (colourless) to 'Z' (yellow/ brown). Most diamonds used in jewellery are nearly colourless with pale tints of yellow or brown.
Clarity
The clarity of a diamond, relates to the amount of inclusions found within the diamond. Inclusions are non-crystallised carbon marks found within a diamond when the the diamond was formed 3 billion years ago.
The fewer inclusions a gemstone has, the higher its clarity grade and the more valuable it is.