If you've ever shopped for a gem, you've probably read a few terms that didn't make much sense. Bezel, pavilion and crown are three common terms used to describe the cut of a gem, but there are many more. Most of the time these terms will be used with ratings and ratios, but are useful for understanding how to judge a gem's cut.

When discussing the actual cut of the gem, people typically mean shape, such as round, heart or oval. However, the term cut actually refers to the gem itself, the ratios used in the cut and how it was finished. Following cut, the make of a gem refers to the quality of the actual finished product, and finish refers to the polishing done to the cut stone.

The shape of the gem can be referred to by many terms. A brilliant cut is usually a circle where the facets are arranged facing the center, to maximize the reflection of light. A radiant cut usually has 70 facets which are arranged in a rectangular pattern.

The cut of the gem has several elements that describe how it looks, is composed and will reflect. The crown is the top of the gem, or the part above the girdle. The girdle is the widest area of a stone and separates the crown from the pavilion. The pavilion is then the bottom of the stone, or the portion that will be set in the jewelry. The crown is typically comprised of facets, or flat surfaces that have been polished.

There are several terms to describe the characteristics of the gem. An inclusion is any internal characteristic of the gem. Inclusions can be mild and lend the gem a certain unique character, or they can be so pronounced that the gem is considered a dead stone. Dead stones are so badly marred that they have no luminosity. An internal characteristic is any observable imperfection within the gem.

Usually when purchasing from a store, you will hear about the 4 C's, which are cut, clarity, color and carat. The clarity of the stones refers to a lack of imperfections within the stone. Color refers to the hue and dominant shade of the gem, which should be uniform and vivid. Carat is a unit of gem measurement, and reflects the weight of the gem.

You may also hear about the gem's fire or brilliance. This is simply the amount of light the stone reflects when viewed from the top. A stone that glitters under light is considered to be very brilliant. This can also be measured in internal reflection, the amount of light that in reflected from the interior walls of the stone. Stones that have a good fire are sometimes said to be lively.

It's a good idea to have an understanding of the commonly used terms, but don't be afraid to just describe the gem. "Sparkly", "bright" or "pretty" are perfectly acceptable. The specifics of the gem aren't as important as whether or not you find one that you enjoy.