The Butterfly CutThe Butterfly Cut

The Gemstone Butterfly Cut


The Gemstone Butterfly is a stunning design for a custom-cut gem. Our step-by-step guide will show you how to facet this piece and suggest some variations.

2 Minute Read

The Gemstone Butterfly cut goes together simply, and the results are stunning. Obviously, the larger the gem, the more visible your butterfly will be. This has been cut as small as 8 mm, but 10 mm and up is preferable.
The Butterfly Cut
The Gemstone Butterfly Cut

Comments

The Gemstone Butterfly was originally designed with 42º pavilion mains. Even though a majority of the pavilion is cut at this angle, it has very little brilliance. In this variation, it has been made thinner, as if you were going to cut it in garnet or some other dark material. Here, the emphasis is on the design, not brilliance. It can be converted back to 42º mains, or made thinner to accommodate your rough. Use the "keep your distance" rule" and add or subtract the same amount to each setting.

The Gemstone Butterfly: A Step-By-Step Guide

StepAngleIndex
190º02-07-11-16-21-25-30-34-39-43-48-53-57-62-66-71-75-80-85-89-94
245º02-07-11-16-21-25-30-34-39-43-48-53-57-62-66-71-75-80-85-89-94
335º02-07-11-16-21-25-30-34-39-43-48-53-57-62-66-71-75-80-85-89-94
432º37-59
532º30-66
632º16-21-26-70-75-80
733.4º09-87
833.8º96
934.2º46-50
  1. Create girdle.
  2. Girdle facets.
  3. Leave frosted. These facets outline the design and also determine how far in the edge of the wings are.
  4. The first wing facets are cut to the edge of the 45º facets in Step 2.
  5. Cut the remaining wing facets to the outer edge of the previous wing facet. They will not meet perfectly in the center.
  6. Cut the remaining wing facets to the outer edge of the previous wing facet. They will not meet perfectly in the center.
  7. Cut the remaining wing facets to the outer edge of the previous wing facet. They will not meet perfectly in the center.
  8. This is the abdomen. Cut on the pre-polish lap and position by eye.
  9. The antennae are very tiny. Cut on the polishing lap!

Techniques

The butterfly is highlighted by leaving the surrounding facets frosted. While that may seem pretty straightforward, there is a trick to the technique. Essentially, you want to bring them down to as fine a finish as possible without taking them to a semi-polished look. Usually, you can do this with a 1,200 lap, but you may need to use a 600 in some cases.

Why should you avoid the semi-polished look? Because once you reach the polishing stage, if you try to polish next to a much rougher surface, like a 360, small bits of the rough will break off and scratch your facets. Worse yet, they could get embedded in your polishing lap!

You'll notice I haven't listed any crown settings. In the diagram below, the crown is step-cut with two rows of facets cut at 35º and 25º, using the index setting in Step 1. In a design like this, leaving the table as large as the interior design is usually desirable. That isn''t a high priority in this case. I have cut these with the crown facets overlapping the wing tips and the results are not only satisfactory but also quite pleasant.

The Butterfly Cut - Three Views

If you have the skill, try to cut a domed crown with cabbing equipment. Remember, the thinner the crown, the more the butterfly will be magnified.


Donald Clark, CSM IMG

The late 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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