What is it?

Tool included in 3D Artisans for Grasshopper, which allows creating brilliant cuts of rounded, oval, pear, marquise or cushion profiles, with the particularity that it not only generates from mathematically ideal girdle profiles but also from irregular profiles: deformed rounded, bowtie oval, elongated pear, asymmetric marquise, etc.

Brilliant Cut is especially useful for CAD reproduction of real gems, which is gems whose fillet profile does not obey ideal mathematical patterns such as the circumference (round brilliant) or the ellipse (brilliant oval), but the particular girdle profile with which the gem has been cut. Unlike the tools available in the most popular jewelry plugins, the Brilliant Cut tool by 3D Artisans allows you to reproduce real gems in CAD. The need and development of this tool is the result of the limitations found in commercial jewelry plugins, which only allow cuts to be created from ideal mathematical profiles.

Here is a sample of the capabilities of the tool. In the first row, sizes with an ideal profile have been created. In this case, the Brilliant Cut provides the same results as commercial plugins. In the second row gems have been created with slight deformations with respect to the ideal profile, that is to say, just like real gems. Commercial jewelry plugins do not generate these types of cuts. Less common gems with extreme deformations have been created in the third row to explore the tool's potential.



How is it used?

First, a previously created curve corresponding to the girdle section must be selected. By default, a gem will be created with the standard parameters of table size, crown height, pavilion height, girdle height, culet size and position. The gem is obtained in two formats, polysurface, and mesh. The previous parameters can be modified by setting the Ideal parameter to False and entering the new values ​​in the corresponding input. It also allows determining if the fillet is faceted or not.


  • Girdle shape: Curve corresponding to the girdle section of the gem.
  • Ideal: If TRUE, it sets the standard parameters. If FALSE, it takes the parameters indicated in the following Inputs.
  • Table size: the shortest dimension of the table in absolute values.
  • Crown height: height of the crown from the girdle in absolute values.
  • Pavilion height: height of the pavilion from the girdle in absolute values.
  • Girdle height: girdle height in absolute values.
  • Girdle faces: If TRUE, the girdle facets appear.
  • Culet size: determines the shortest dimension of the culet in absolute values.
  • X move culet: movement of the culet on the abscissa axis.
  • Y move culet: movement of the culet in the ordinate axis.


  • Brep: gem cut in Poysurface format.
  • Mesh: gem cut in Mesh format.
  • Girdle shape: Curve of the girdle section at the new location.

Downloads for users with knowledge of parametric CAD

If you want to create parametric design projects with this tool, download 3D Artisans for Grasshopper from the corresponding page.


Downloads for users with no knowledge of parametric CAD

If you are not a parametric CAD designer but want to try and use the tool freely to create your brilliant cuts, you can download the BrilliantCut.gh file here. This license allows you to commercialize the projects generated with this tool, but not commercialize the tool.


Creative Commons License
Brilliant cut by Carlos Serra is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
Based on a work at www.3dartisans.com/downloads/BrilliantCut.gh.
Permissions beyond the scope of this license may be available at www.3dartisans.com/index.php/en/products/brilliant-cut-2.

To run the file do the following:

  • From Rhino's Tools menu, select Grasshopper.
  • In the Grasshopper File window, select Open Document.
  • Open the downloaded file Briliantcut.gh
  • In Rhino, draw a girdle section curve and select that curve.
  • In the document opened with Grasshopper, press the Cut Preview button. Rhino shows a preview of the cut.
  • If you want to modify the cut, set the Ideal Proportions button to False, and modify the rest of the parameters.
  • To get the final model in Rhino, run the Bake Solid or Bake Mesh button from Grasshopper.
  • We recommend that you keep a backup copy of the file. These files are not protected and abnormal use can make them unusable. In case of failure, reload the backup copy.