All About Faceted Emeralds

Anatomy of a Gemstone

All faceted emeralds (and other gems) are divided into three parts: the crown, girdle, and pavilion. There are names for the individual facets on the crown, but the girdle and pavilion are situational. The girdle is almost never faceted, and when it is, it is called a faceted girdle. No further names. The pavilion has names only when it has a round-brilliant cut, which is the cut most diamonds have.

Emeralds are never given that cut on the pavilion, with most cutters preferring a modified step cut. Step cut is what the pavilion of the emerald cut has.

Crown Facets

Table Facet

Kite Facet

Star Facet

Upper-Half Facet

Pavilion Facets

The case for most round cut emeralds is a modified step cut. This modified step-cut on the pavilion allows for shallower rough to be cut, and also gives the cutter much more flexibility in orienting the emerald when cutting. Curving the cut like this also allows the gem cutter (formally called a lapidary) to retain more carat weight from the original stone.
Retaining carat weight is important, since even the best lapidary usually loses about 50-70% of the carat weight from the rough gems. For the lapidaries, every cut shaves away from the price of the final gem, impacting their bottom line.

While the round-brilliant diamond cut is not used for most gems (other than diamonds), colored gems occasionally get faceted like this. The lower half facets meet the similarly named upper-half facet, with the pavilion mains each meeting the tips of the kite facets and converging in the center below.

Sometimes the point where all the pavilion mains converge will have a small cut called a culet to reduce chipping. This cut is up to the preference of the cutter, and may or may not be present for any given round-brilliant cut.

Common Gem Cuts

Most gem cuts have a crown like a round brilliant, and a pavilion with a modified step-cut.

Aside from the namesake emerald cut shown at the beginning (which is faceted in an entirely different way), the most common cuts are the oval and cushion. They are the most versatile cuts a lapidary has, though sometimes other shapes like pear and marquise will make better use of the given carat weight. Hearts are very common too, though they are a more complicated cut. Also note that the pavilions of all of these gems are a type of modified step cut.

Again, aside from the shapes, the faceting of all of these gems are very similar in appearance.

Cut Variations

While the following cuts have different names from the emerald cut, for the cutters they are mostly the same technique. Some of these are seen much more frequently than others.

Asscher

Octagon

Radiant

The asscher cut is essentially a square emerald cut. An octagon cut just has corners equal to the length of the sides, and thus is an octagon shape that is very rarely seen despite using the same cutting techniques as an emerald. The radiant cut on the other hand refers to more than the square shape of the emerald (radiant cut can be rectangular too). This includes how the crown and pavilion are faceted like a square version of a radiant cut.

Radiant and Mixed Cuts

The radiant is different from the emerald cut due to how a radiating pattern is seen on the pavilion. Radiant cuts can also be square like a princess cut, but the corners are cut off as shown above.

Princess Cut (Crown)

The key difference between a princess cut and a square radiant cut is whether the corners are cut off or not. The crown does not necessarily have to have certain cuts either, which leads into mixed cuts. Mixed cuts are self-descriptive, being different cuts put together. Lapidaries frequently do this, usually with the goal of maximizing the weight of the gem they are cutting. They will also take special requests from dealers and customers, though an additional fee and agreement to buy said gem will be required. This is especially true for unusual cuts that cannot be categorized with other cuts.

Emeralds are the least likely to have crazy cuts due to how they frequently form with fractures, which makes them less tough than other gems. This doesn’t mean they’re weak though; in comparison to your finger, your finger will be broken long before the emerald is.