DIAMOND SHAPE Since all diamond cut styles are very different, unique characteristics determine quality for each shape.
The round brilliant cut diamond is by far the most popular and most researched diamond shape available today. For almost 100 years, diamond cutters have been using advanced theories of light behaviour and precise mathematical calculations to optimise the fire and brilliance in a round diamond. In addition to being the most popular and researched shape, round-cut diamonds will typically give you more flexibility in terms of balancing cut, colour, and clarity grades while still getting the fire and brilliance you want. To maximise the brilliance of a traditional round diamond, select one in the two highest cut grades, ideal or very good, and choose ideal, excellent, or very good polish and symmetry grades. For a round diamond with superior sparkle, consider an Astor by Blue Nile™;
This is our most popular non-round diamond. Its beautiful brilliance and unique cut makes the princess-cut diamond a favourite for engagement rings. The princess has pointed corners and is traditionally square in shape. When choosing a colour grade, consider that while the price of a J-colour non-round diamond is exceptional, colour may be slightly visible in its corners. Also, princess-cut diamonds can vary greatly in how square or rectangular they are. To find the dimension of princess you want, look for the length-to-width ratio in our interactive diamond search and on each diamond’s detail page. This will determine what the diamond will look like when viewing it from above. Here are length-to-width ratios for princess-cut diamond shapes that are pleasing to the eye. For a princess diamond shape that is square, look for length-to-width ratios between 1 and 1.05. If you prefer more of a rectangular shape, look for length-to-width ratios greater than 1.10. For a princess diamond with superior sparkle, consider an Astor by Blue Nile™diamond;
What makes the emerald diamond shape different is its pavilion, which is cut with rectangular facets to create a unique optical appearance. Due to its larger, open table, this shape highlights the clarity of a diamond. If you choose an emerald-cut diamond with a lower clarity grade, such as SI, be sure to review the clarity plot on the diamond certificate. Also, emerald-cut diamonds can vary greatly in how rectangular they are. If you’d prefer an emerald cut with a squared outline, look for an Asscher-cut diamond. To find the shape of emerald diamond you want, look for the length-to-width ratio in our interactive diamond search and on each diamond’s detail page. The length-to-width ratio will determine the diamond’s outline, or what it will look like when viewed from the top. For the classic emerald-cut shape, look for a length-to-width ratio between 1.30 and 1.40~