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Types of Cuts for Rubies

Rubies possess among the richest colors in the gemstone world. Formed of compressed aluminum and oxygen, true rubies are always deep red. Those of any other color are not true rubies, though they may have formed in the same gem beds. They are also one of the hardest gemstones in the world, which is why cutting rubies is a precise and difficult art. The best cuts are called perfect cuts, referring to a stone that refracts light both on the surface and within. Typical cuts are middle of the line cuts that refract only a little light. Fish-eye cuts are the lowest grade; they make the gem look greasy and transparent. A skilled jeweler can cut a ruby into any shape and create a perfect cut.

Brilliant Cut
- This cut is one of the most popular for ring and earring settings. The shape is typically circular with a flat octagon cut into the top center. Radiating out from the octagon are small, uniform, triangular facets that round the top of the ruby into a gentle curve. The back of the stone is tapered to a point in a series of very long, triangular facets. When you look down on the back of the stone from above it should look like a starburst. Diamond-cut rubies usually have 58 facets in total, but the number of facets can vary if the ruby is not specifically marked as being diamond cut. Since the ruby has such deep color, this cut does not sparkle as much as other cuts, though it looks pretty in symmetrical settings.
Cabochon Cut
- Cabochon-cut rubies look like domed ovals with a flat back. This cut is not faceted but carefully smoothed and polished. Though you can see through this kind of cut easily, it is usually backed with a silver or other metallic setting to help give it sheen. Since they don't sparkle or reflect much light, cabochons are among the less expensive cuts. They work well in patterns such as flowers or as side settings to a more elaborate stone. They also look good in settings that hold them in place with wire scrolls and designs.
Emerald Cut
- This cut resembles a rectangle with rounded corners. The top of the ruby is flat and perfectly rectangular. Facets along the sides are long, narrow rectangles that taper the edges of the stone downward. At the corners, the facets are shaped like very small trapezoids. The back of an emerald-cut ruby has slightly wider rectangular facets along the edges and very narrow triangular facets at the corners that push the bottom of the stone into a point. These make popular center settings in rings.
Heart-Shaped
- Heart-shaped rubies are among the most expensive cuts because they require a lot of cutting. These many small facets, however, almost always create a perfect cut that refracts light on the surface and in the center. Rubies are also popular heart-shaped stones because they are red, making them the perfect symbol for love. The top of the stone is a flat heart with triangular facets of varying sizes forming the tapered and heart-shaped edge of the stone. The back of the stone is a series of long, tapered triangular facets that bring the back to a sharp point.

Rocks & Minerals