How To Add Sparkle To An Emerald Cut


Emerald Cut Emerald
“Emerald and diamond ring,” faceted emerald gemstone, emerald cut, handmade 18k yellow gold ring and platinum wire settings, by gemteck1 is licensed under CC By 2.0

An emerald cut is an excellent choice for gemstone weight retention and color enhancement. However, as a trade off for these qualities, it’s sadly lacking in brilliance, sparkle, and life. Emerald cut stones simply sit there with nice color and occasional broad flashes of light. As a custom gem cutter, I usually strive for a dazzling display of light. I’ve always been somewhat disappointed with my emerald cuts. It became a challenge of sorts for me to find a way to add sparkle to these shapes. After a few years of experimentation, a solution finally came clear. I developed a technique that adds life to emerald cuts with only a minimal sacrifice in weight.

The first design based on this technique was for gems of standard proportion. I was very pleased with it. However, I still faced the challenge of what to do with some very long crystals of tourmaline and aquamarine I had in stock. The normal approach would be to cut them as long baguettes or saw them in half to create two smaller, but better proportioned, gems. Neither of these solutions satisfied me. I kept at it until I found a way to apply my sparkling emerald cut technique to very long crystals.

These cuts make use of vertical facets and a curved keel. The finished gems usually have one very bright spot, which may be accompanied by a less bright spot on either side. At first, I was disappointed with this effect. My opinion changed, however, after I carried one of the gems around and saw it in different lighting situations.

With this technique, the majority of the light entering the gem is focused into a single brilliant spot of light. This results in brilliance in soft light situations where most cuts would simply turn dark. That single point of light is also incredibly animated. It races from one end of the gem to the other with astonishing speed. The sparkling emerald cut technique doesn’t yield finished gems as dazzling as more symmetrical gems. However, this technique is a significant improvement over a standard emerald cut. It’s very practical for wear, especially for softly lit evenings. And as an added bonus, the facet size is reduced for easier polishing.

Emerald Cut Sapphire
“Sapphire,” emerald cut, 1.07-ct. © Dan Stair Custom Gemstones. Used with permission.

The Sparkling Emerald Cut Pavilion: Step-By-Step

This design is shown with a 96 index gear and can be used on any proportioned gem. It’s quite easy once you have cut one or two stones. The mains adjust very easily during pre-polish, so you have room for error in the first cutting.

Sparkling Emerald Cut Pavilion

  1. Begin by shaping the outline at 90º.
  2. Create a girdle by cutting a row of facets around the stone at 65º.
  3. Set your angle for the pavilion mains (42º or 43º). Cut a set of facets at indexes 1 & 95, 47 & 49, until they close the culet. Then cut another set at indexes 2 & 94, 46 & 50, bringing them about a millimeter from the center. Keep cutting sets beginning with I 3, another at I 4, etc., until you run out of room. Be careful as you get near the ends, as these facets come down to the girdle in a hurry.
  4. Finish the mains by raising the angle ½ a degree and cut two facets in the center at I 96 & 48.
  5. You will then have to add another facet or two on the sides (55º or so) to blend the mains into the girdle facets.

The Sparkling Emerald Cut For Long Crystals

This cut is great for those long tourmalines and aquamarines. It’s brought many ooh’s and aah’s from jewelers who’ve seen the results. With 46 facets on the pavilion, the sparkle and brilliance are outstanding.

Sparkling Emerald Cut - Long Crystals

Follow the steps in the table below.

PAVILION

Step Angle Index
Girdle 90º 030-090 length
Girdle 90º 120-060 width
Girdle 90º 002-058-062-118
Girdle 90º 004-056-064-116
5 48º 120-060
6 48º 002-058-062-118
7 48º 004-056-064-116
8 70º 030-090 ends
9 46º 001-059-061-119
10 46º 003-057-063-117
11 44º 001-059-061-119
12 44º 003-057-063-117
13 43º 120-060
14 43º 002-058-062-118
15 43º 004-056-064-116
16 45º 120-060
17 45º 002-058-062-118
18 45º 004-056-064-116

Steps one through four: create a level girdle. As you cut one through three, aim to get all three facets the same width, as viewed from the side.

Steps five and six: split the girdle facets and get cut to the girdle. Where those facets meet is where you cut to for steps seven through eleven.

In the diagram, those meetpoints have been cut over by facets twelve and thirteen. However, it will be obvious when it’’s on the dop.

For the last three steps, simply trim off corners. (These steps are only used on very large gems).

To finish the crown, step cut it with the same indices used for the girdle.

Happy Faceting!

Emerald Cut Tourmaline
“Bi-Colored Tourmaline,” blue-green to green, emerald cut .94-ct, Afghanistan. © Dan Stair Custom Gemstones. Used with permission.

About the author
Donald Clark, CSM IMG
Donald Clark, CSM founded the International Gem Society in 1998. Donald started in the gem and jewelry industry in 1976. He received his formal gemology training from the Gemological Institute of America (GIA) and the American Society of Gemcutters (ASG). The letters "CSM" after his name stood for Certified Supreme Master Gemcutter, a designation of Wykoff's ASG which has often been referred to as the doctorate of gem cutting. The American Society of Gemcutters only had 54 people reach this level. Along with dozens of articles for leading trade magazines, Donald authored the book "Modern Faceting, the Easy Way."
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