Ruby ID: R11953
Origin: Myanmar (formerly Burma)
Faceted rubies are the form of gem that most individuals are familiar with, both with rubies and with most other gemstones. Few realize that only scarcest and most brilliantly colored material is used to make ruby jewelry, and that brownish and opaque material is called “ruby” too.
Rubies that reach Pigeon’s Blood red are popular to the point that many are willing to buy material treated to this condition since the natural, untreated appearance of rubies is prohibitively expensive.
Most rubies will be cut into a cushion shape as shown here. A few other common examples are oval, round, and emerald (this cut was developed for emeralds, but is frequently used for other gems).
R12145 | play
Myanmar (formerly Burma)
R11955 | play
Myanmar (formerly Burma)
R10011 | play
The cut names usually refer to how the gemstone is shaped, rather than the specifics of the cut. Cuts for faceted gems are usually divided into three parts: the crown, girdle, and pavilion.
In most cuts, the crown is often a type of modification of the basic round-brilliant cut (the round cut most diamonds get), with the exception of emerald cut. There are other exceptions, but they are infrequently seen and will be discussed later in the article.
There are even names assigned to the individual facets on the crown and pavilion. The girdle is typically not faceted, and when it is, the term is “faceted girdle”.
Ruby ID: R11212
On the topic of round cuts, the pavilion is very different between round diamonds and round rubies.
A cut for a diamond will have two to three types of facets. The pavilion mains come to a point on the pavilion, while the lower-half facet meets the upper-half facet at the girdle. While not shown here, sometimes there will be a very tiny cut where the pavilion mains meet. It is called a culet, and helps prevent chipping in this spot.
For rubies (and other colored gems), the cut on the pavilion lacks names for the individual facets. Very often it is a modified version of a step-cut (like in emerald cuts) that is much more versatile for the cutter. When dealing with most other elongated cuts like oval, cushion, emerald, etc, the point where the facets on the pavilion converge is called a keel line (think where the culet would be on a diamond, except pulled into a line).
With other cuts like radiant, princess, modified brilliant, and many more, the pavilion facets are specific to the cut. Emeralds almost always have an unmodified step cut too.
R5654 | play | “Ruby ID: R5654”
R11965 | play | “Ruby ID: R11965”
R10034 | play | “Ruby ID: R10034”
R10071 | medium | “Ruby ID: R10071 , Weight:1.05 Carats , Origin: Madagascar”
While a little dark, this ruby has the princess cut on the crown and pavilion. The diagram for the pavilion looks like this:
The square cut is called a princess cut. The difference between a princess cut and an asscher cut is the princess still has corners, while the asscher does not.
This princess cut ruby is a little different, since the pavilion has a step-cut (like emerald and asscher) instead of a matching princess cut. When dealing with the less common cuts, mixing and matching different faceting styles between the crown and the pavilion is fairly common.
The crown of the radiant cut is like a brilliant cut with an emerald shape. The pavilion has the same type of cut as a princess but elongated to fit the rectangular shape.
These radiating facets on the pavilion are known for their brilliant sparkle, but this cut was designed for diamonds. Most gem cuts are. This leads to them being modified between different gemstones.
R9046 | play | medium
R3744 | play | medium
Any cut with an exceedingly unique shape that cannot be categorized otherwise is referred to as a “fancy cut” or “designer cut”. These cuts can look like just about anything possibly imagined, though they are typically reserved for more common gems like ametrine (a type of quartz that is naturally purple and yellow), or aquamarine.
Cuts are frequently adapted for different shapes, though this is less common in rubies due to how high their average per-carat price is. The more expensive the gem, the less likely it is to receive an unusual cut. Gem cutters will take personal requests within reason, and with a guarantee of purchase. They will not facet gems into weird cuts if those gems cannot be sold.