What transforms a diamond into a dazzling gem is the cut. Facets are cut into the diamond at different angles to refract light. A well-cut diamond appears brilliant and fiery.

Pure diamonds are graded from D (colourless or bright white) to Z (yellow brown). The most expensive are colourless diamonds. At The Engagement Room, we focus on the higher grade diamonds, generally between D and H.

Clarity is another measure of a diamonds value. Because diamonds are formed deep within the earth, under extreme heat and pressure virtually all diamonds contain 'birthmarks' – small imperfections on or inside the diamond. Diamonds which contain numerous or significant inclusions or blemishes have less brilliance because the flaws interfere with the path of light through the diamond.

Diamonds, like other gemstones, are measured by weight or carats. Sometimes a higher carat diamond doesn’t look the largest, because the size it appears can be dictated by the shape.

Another key decision is the metal your precious diamond is set in. The two main colour options are yellow gold, which is the classic choice for engagement rings and works well with warmer skin tones and white gold (or platinum), which has a contemporary feel and blends well with other jewellery.

There’s no magic number and whether your budget is $2,000 or $200,000, there are endless options. Many couples prefer to make the decision of how much to spend on their engagement ring together.