A turned girdle is a girdle with a smooth round edge, shaped as a cylinder, instead of flat girdle facets. CAD often gives a round stone this kind of girdle.
In more detail
A turned girdle is one surface in a solid but many facets on a faceting machine. So a cut page can give two facet counts.
How we measure it
Our tools read a STEP cylinder as a ring of flat facets with the same cross-section area.
Related terms
- Facet count: The facet count is the number of facets on a cut. On our cut pages, it is the number of planar faces of the cut's STEP solid.
- STEP file: STEP is a standard CAD format that stores an exact solid, with each facet as a true plane. CAD programs such as FreeCAD, Rhino and Fusion open it to measure a stone and design a setting.
- Girdle: The girdle is the narrow band at the widest part of a cut stone, between the crown and the pavilion. It is the edge that a setting grips.