Proprietary step cuts

These cuts have straight facet edges that generally run parallel to the girdle. The emerald cut is the best-known type of step cut. The first emerald cuts were the ancient table cut or trap cut, made around 500 years ago from well-formed glassy octahedral diamond crystals. A table was ground on to each of two stones by rubbing two crystal points together.

Step cuts have straight edges, with square stones being cut from regular octahedra, and rectangular stones from deformed crystals or where inclusions have been avoided in the polished diamond.

Reputed for their clean, sophisticated look, most step cuts have fewer facets, and fewer but larger flashes than the radial-faceted brilliant-style square-shaped cuts.

Clearly there are many more radially-faceted brilliant-cut proprietary diamonds in the market than there are proprietary step cuts – this is because there are fewer original faceting patterns for step cuts than other shapes. In addition, any small symmetry deviation in most step cut styles is visually apparent to the naked eye, so there is less opportunity for a diamond cutter to “push the yield” or “swindle” the rough diamond.

As seen in the chart, step cuts have fewer facets than brilliants. That, combined with the fact that there is less interaction between the facets, means inclusions are much easier to see in step-cuts.

In the past decade, there have been a few attempts to create step-cut diamonds with more sparkle and facet interaction.

Most of the new creations include the use of scissor type or diagonal facets and, for that reason, these have been included in the step-cut category.

The scissor facets can split what would have been a single facet into two, three or even four facets with diagonal facet lines. This does not create the brilliant effect from true radial-faceting placement, but does allow more interplay between facets to create smaller sparkles.

A few of these cuts have been actively promoted in Australia. Some have had commercial success if for no other reason than they are clearly different.

Differentiation of diamonds themselves could be a crucial issue for the long-term viability of the diamond industry. Around half the world’s diamonds are cut and polished into the 57-facet round-brilliant cut – essentially we commoditise diamonds and only differentiate them via their jewellery design. Introducing visually-different variations of diamond cuts can help drive consumer demand.

A famous example of a step cut is the Asscher – first patented in 1902. This cut has made a fashion revival since. In 1999, the same design with additional facets was patented and called the Royal Asscher, since Queen Juliana of Holland granted the Asscher Diamond Company royal title in 1980.