The second group of faceted cuts includes straight-sided girdle shapes: squares, rectangles, octagons, triangles, trapeziums, hexagons and barrels. These forms are traditionally cut as a series of rectangular parallel facets that follow the shape of the girdle in a stepped arrangement – hence the term step cut.
This very old cut was originally developed for diamonds, but is now used primarily for Emeralds as the result is a more colorful but less brilliant look. A rectangular step cut with corners cut diagonally an octagonal shape is an emerald cut, used to display the emerald’s colour and protect the fragile stone from damage. In rectangular step cuts, the culet takes the form of a ridge rather than a point.
Rarely used in uncolored stones.
The cross cut (or scissor cut) is a modification of the step cut, in which the steps are divided into triangular facets that introduce more light and life into the gemstone. This cut is commonly used to improve weak or dark stones. The cross cut can also conceal flaws in the outer areas of the stone and will help hide a “window” in a shallow gem.
Another modification of the step cut is the French cut. It is used on small stones (less than ¼ in/6mm) with rectangular, square and triangular shapes. Ruby, sapphire and emerald are this way for channel setting or use in line bracelet and necklace designs.
Fancy cuts were originally devised to retain maximum weight in irregularly shaped crystals or in material that had been cleaved from larger crystals. Nowadays, however, fancy cuts are design-led. They create different optical effects, such as mirror cuts and prism cuts, and may also be variations of existing cuts. For example, the crown of step-cut or brilliant cut gemstones is frequently modified – the surface can be faceted with small squares in a low-domed chess cut or cut like a cabochon with a smooth buff top. Sometimes fancy cuts are used to disguise faults, so examine them closely.