A Guide to Gem Cutting Styles

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PinkDiamond
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A Guide to Gem Cutting Styles

Post by PinkDiamond »

There are a lot more styles of cuts than the public gets to see in jewelry stores. Here are some a few may not even be aware of, in addition to the usual shapes, and you'll learn what the facets are called and where they're placed, in this article from the International Gem Society. Enjoy! ;)

A Guide to Gem Cutting Styles
by Donald Clark, CSM IMG, Phoebe Shang, GG

Step 1: Introduction to Gemology
Lesson 23


Summary

While some cut names may describe the face-up shape of the finished gem, others refer to the shape and arrangement of the gem’s facets. These cuts are also known as gem cutting styles. The three most basic cutting styles are brilliant, step, and mixed. For example, a “round brilliant diamond” has a round shape but a brilliant cutting style. Faceters can combine these styles to create many different gem designs.
Reading time: 9 min 36 sec


Image
A trilliant-cut smoky quartz, 8.92 cts, 14.05 x 14.05 x 8.69mm. Gem cutting and photo by Peter Torraca. Used with permission.

Image
(1) Round brilliant, top view (2) Oval brilliant, top view (3) Rose cut, top view (4) Round brilliant, side view (5) Cushion brilliant, top view (6) Rose cut, side view (7) Step cut, octagon (8) Pear brilliant, top view (9) Step cut, oblong (10) High cabochon, side view (11) Cabochon, side view (12) Lentil-shaped, side view. Gemstone Cuts. No known copyright restrictions.

"The Three Basic Gem Cutting Styles

Brilliant Cut

Brilliant cuts consist of triangular and kite-shaped facets that spread outward from the center of the gem. As befits its name, the brilliant cut gives off the most scintillation of any cut.

Image
Round brilliant facet chart. Image by Jasper Paulsen. Licensed under CC By-SA 3.0.

Step Cut

Step cuts consist of rectangular facets that ascend the crown and descend the pavilion in steps. Examples of step cuts include emerald and baguette cuts. These are popular because they show off the stone’s color and clarity and produce a subtle gleam.

Image
Emerald cut. Image by Ducky. Licensed under CC By-SA 3.0.

Mixed Cuts

Mixed cuts combine step cut and brilliant cut styles. They have brilliant facets on the crown and step facets on the pavilion, or vice versa. Mixed cuts may even combine cabbing and faceting techniques.

Image
Mixed-cut oval citrine. Photo by Wela49. Licensed under CC By-SA 3.0.

Shape and Style Combinations

Faceters can combine the above cutting styles with almost any shape. For example, a square modified brilliant is a princess cut. A square step cut with beveled corners is an Asscher cut. A square mixed cut is a Barion cut.

Step and mixed cuts apply to fancy shapes only. No step-cut or mixed-cut rounds exist.

Of course, you can also find variations within all shapes. A triangular gem can have many or few facets, much or little brilliance and scintillation, etc.

Rose Cut

While brilliant and step cuts currently enjoy the most popularity, the rose cut is a unique style important to gem-cutting history. Dating back to the 16th century, the rose cut has a round, cabbed flat base and a faceted top. (Occasionally, you’ll see a gem with a faceted pavilion and a domed crown. However, this isn’t a standard cutting method).

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Rose cut

Triangular facets rise to form a shape like a faceted mound. While the number of facets on each rose cut varies, the face-up shape is almost always circular. For 16th-century cutters, roses maximized the use of flat rough and created gems with more brilliance than previously seen.

Image
Rose cut facet chart. Fig. 157-160 round rose, 161 oval rose, 162 drop rose, 164 side view of rose. No known copyright restrictions.

However, this cut ... "

https://www.gemsociety.org/article/gem-cutting-terms/
PinkDiamond
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crazy8s
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Re: A Guide to Gem Cutting Styles

Post by crazy8s »

Enjoyed reading this, and loved the pink topaz necklace. :D
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SwordfishMining
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Re: A Guide to Gem Cutting Styles

Post by SwordfishMining »

Nice. There is a name for colorless opal that displays color when properly lit.....Contra Luz.
I'll jump over my shadow. https://www.virginvalleyopal.com"
Opals & more at my ESTY store https://swordfishmining.etsy.com"
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rocks2dust
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Re: A Guide to Gem Cutting Styles

Post by rocks2dust »

Softer gem materials may also receive cabochon cuts, since cabs don’t show scratches as easily as faceted gems do.

Um, yeah cabochons do easily show scratches. Facets can be good at hiding small scratches, whereas they are glaring on the same gemstone given a cabochon cut. Scratches may not be obvious on a highly patterned stone that has been given a cabochon cut, but that is beside the point (a highly patterned faceted stone would equally well hide scratches).

BTW, some cuts lend themselves particularly well to showing off interesting inclusions: e.g., step cuts with large tables (including baguette and emerald), buff-top cuts (cabochon tops and faceted pavilions), tablet cuts (no pavilion; crowns on top and bottom), crownless, etc. One shouldn't have to plop the gem into an immersion cell in order to explore the interior world of stones where the inclusion is the main point of interest. I've seen some fascinating inclusions irretrievably ruined by cutters who seem to be more enamored by the cut than the stone.
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