Diamond Shopping Guide - Cut

If the stress of picking out the perfect ring weren't enough, you also have to learn a whole new vocabulary – the four C's of diamond shopping. Since it's the one piece of jewelry she'll be wearing every day for the rest of her life, it's important to make an informed decision. Buying a diamond can be confusing, and you want to know exactly what you're talking about when you meet with a jeweler. So, we've broken it down into plain English so you'll be fully prepared.

For this post, let's take a look at the cut of the diamond.

Cut = Angles

Here's a little glossary of terms about cut. We'll work from the top down:

Table – The flat surface on the top of a diamond
Crown – The sloped part of the top of the diamond coming off of the table
Diameter – the width of the diamond measured through its widest part
Girdle – the narrow rim going around the widest part of the diamond that separates the top from the bottom. This is where the diameter of the stone is measured.
Pavilion – The bottom part of the diamond, below the girdle. Also referred to as the base.
Cutlet – the point on the bottom of the diamond.
Depth – the total height of the stone, from the top of the diamond (the table) to the bottom (the cutlet).
Brilliance – basically the diamond's fire or radiance. A stone's cut dramatically affects its brilliance.

The diamond's cut is possibly the most important of the four C's. The cut is all about the angels and proportions of the diamond rather than the shape (ie princess, emerald, etc). The diamond's cut does affect how the diamond looks. So, when a jeweler refers to the diamond's cut, they're talking about its reflective qualities, not the shape of the stone.

If it's cut correctly, the light that enters through the stone's surface or "table" will be reflected back out through its surface. However, if a diamond is cut too shallow or too deep, the light will escape through the bottom or sides of the stone, reducing its brilliance. A stone with a good cut has that fiery glittering effect that makes diamonds so mesmerizing. For buying purposes, cuts have been broken down into grades:

Ideal Cut - Applies only to round diamonds. Ideal cut diamonds generally have smaller table sizes and create maximum brilliance.

Premium -Premium cut round diamonds are generally comparable to ideal cut round diamonds, but can be a bit less expensive. Premium cut diamonds are also cut to create maximum brilliance.

Very Good - Very Good diamonds reflect most of the light that enters them. In these diamonds, the cut has been compromised slightly in order to have a larger diamond.

Good - These diamonds reflect much of the light that enters them. Here, the cut has been compromised in order to create the biggest stone possible.

Fair and Poor - These stones only reflect a small amount of light that enters them. They have typically been cut for more carat weight.

If the jeweler you're speaking with doesn't seem to know the difference between "cut" and "shape," that's your first indication that you should be looking somewhere else.

*Note: All grading systems from the Gemological Institute of America (GIA)