Although there are a great number of historic and contemporary cuts and shapes, the following are the ones considered the most important today:
Since most gemstones in their rough condition hide their delicate beauty, the process of gemstone cutting is crucial in unveiling nature's wonders to the human eye. The most important techniques are the cutting, grinding and polishing of the stone. This is done to achieve either a faceted or a non-faceted stone, depending on the characteristics and individual features of the precious stone, as well as other factors. During the cutting process, significant portions of the rough gemstone are lost. This is why many gem cutters choose the shape and cut which maximise the finished gemstone’s carat weight. However, other considerations like inclusions, visual characteristics and the cutters own ability can feature into the decision.
Cuts & Shapes
The difference between a gemstone’s cut and its shape is sometimes confusing as the terms are often used interchangeably, even by people in the trade. However, there is a clear distinction between the two concepts. The shape of a gemstone is its outline when looking at it from above, whereas the cut refers to the way the facets of the stone are arranged. They can be arranged to maximise a gemstone’s brilliance and fire, to showcase the stone’s inner world or to draw attention to the special patterns on its surface. As you will discover, there are some cuts which require a certain shape, however, all gemstone shapes can feature a various array of cuts.
The round brilliant cut with 57 facets, or 58 if the culet is faceted, is considered to be ideal for capturing the light within the gemstone and returning it perfectly into the eyes of the beholder. Famously often used in diamonds, this cut was developed early in the 20th century and has enchanted generations of gemstone enthusiasts and proud owners alike.
Also known as the tapered step-cut, this cut was named after the emerald because it fits the gems natural crystal shape best and often results in a higher weight retention and a better perception of the stones inner beauty. Nevertheless, other gemstones, especially within the beryl family, profit from this cut. The shape of the emerald cut is rectangular and incorporates tapered corners. This timeless cut is often prominently featured in centre stones of classic jewellery designs.
A relatively recent development, the princess cut was created to answer a specific challenge of jewellery making. While the more classic cuts for rectangular gemstones, like the emerald cut, strongly emphasise the colour and inner world of a stone, the princess cut, like the brilliant cut in round gemstones, was created to perfectly capture and reflect the light to achieve supreme brilliance. The princess cut is characterized by its profile, which has similarities to an inverted pyramid.
This cut was invented in the early 20th century by the Asscher Brothers in the Netherlands. Sharing some similarities with the classic emerald cut, it was developed to increase the gemstone’s brilliance. The shape of the gemstone is square or rectangular with cropped corners. An Asscher cut is best identified by squares in a concentric array that seem to draw the observer's eye deep into the precious stone’s centre.
The trilliant cut was first introduced as a diamond cut in the early 20th century. It was a successful attempt to modify the classic brilliant cut and adapt it to triangular shaped gemstones. Because of this relationship with the brilliant cut, trilliants (or triangular modified brilliant cut gemstones) usually exhibit an impressive amount of fire. Today, the terms trilliant and trillion generally refer to gemstones in triangular shapes, regardless of their faceting. They come with straight sides, like the original trilliant diamond cut, as well as curved ones, which are often seen in coloured gemstones today.
A special vintage cut, the briolette cut is often seen in gemstones of pear or oval shape. One of the oldest cuts in the world, the briolette is characterised by extended triangular and diamond-shape facets which run all over its surface. Popularized by many celebrities who wore gemstones of this cut in earrings, this timeless design symbolizes elegance, sophistication and nobility.
A cut which dates back to ancient times, the cabochon cut is used in gemstones with strong visual allure on the surface. Usually in oval shapes, cabochons are neither faceted nor technically cut, but shaped and polished into domes that present the intricate structures of gemstones like opals or moonstones. They are mostly chosen to accentuate special optical phenomena's like the cat`s eye or the star effect in certain stones.
Gemstones in a marquise, or navette shape are pointed ovals and often brilliant-cut to enhance the stones natural fire. Believed to have originated in the court of King Louis XV, this elegant shape accentuates femininity and beauty and is therefore regularly seen in graceful rings.
In the mid-20th century, Lazare Kaplan improved the cut for oval shaped gemstones to resemble the round brilliant cut. Since many gemstones are loosely spherical in their rough state, this elegant shape adds the advantage of retaining a larger portion of the gemstones original weight. If brilliant-cut, its facets lead to a brilliant shine that has been recognized and is appreciated even by European royalty.
The baguette, after the French word for stick, with its thin and long shape has a modern flair to it. A baguette shape gemstone is more often than not step cut and not brilliant cut. This means, the facets are not arranged in a fashion to maximise brilliance, but run parallel along the stone. As such, the baguette shape particularly appeals to gemstones whose crystal structure is by nature oblong and allows for the marvellous perception of the precious stone’s depths.
Being the sign of love, this gemstone shape naturally symbolises the strong and intimate bond between two people. The symmetry between the two halves is essential for the quality of gemstones in this shape. Most often faceted to augment the gemstone's brilliance, the heart shape, although seldom chosen for engagement rings, is popular in jewellery bestowed to loved ones as a gift.
The pear, or tear drop shape partly owes its popularity to the fact that rough crystals sometimes tend to be bulky on one side and rather thinner on the other side. However, the shape is particularly well suited for pendants and rings alike. If brilliant-cut, the pear shape conveys elegance and a special appreciation for nature's marvels.
Contrary to popular beliefs, the cushion-shape gemstone is not a modern invention. In fact, based on the so called old-mine cut, it was one of the most beloved shapes during the 19th century and has had a revival in the last decades. Its facets are often larger so as to accentuate the shine and inner beauty of the gemstone rather than to emphasize its brilliance.