Star facets are the triangle-shaped facets that are located directly around the table facet of a round brilliant cut diamond. These facets are an essential component of the diamond’s overall faceting structure and play a crucial role in the diamond’s brilliance and light performance.
Key Characteristics of Star Facets:
Shape and Position: Star facets are triangular in shape, and they are placed above the girdle (the widest part of the diamond), surrounding the table facet, which is the large, flat top surface of the diamond. In a round brilliant cut diamond, there are typically 8 star facets in total – one on each side of the table facet, creating a visual pattern that can resemble a star when viewed from above.
Light Reflection and Brilliance: The main purpose of star facets is to enhance the brilliance of a diamond by reflecting light in various directions. As light enters a diamond and reflects off the facets, it produces the sparkle and scintillation for which diamonds are known. The star facets, along with the other facets in the round brilliant cut, help maximise the amount of light that is reflected back to the observer’s eye.
Arrangement in a Round Brilliant Cut: The round brilliant cut typically features 57 facets (or 58 if the culet is present), and the star facets are an integral part of this highly structured cut. They are strategically placed between the table facet and the upper girdle facets. Their purpose is to capture and reflect light from the top of the diamond, helping to create the sparkling effect.
Visual Effect: When viewed from above, the 8 star facets are positioned symmetrically around the table to form the shape of an 8-point star. This symmetry contributes to the overall aesthetic appeal of the round brilliant cut and plays a part in its popularity as one of the most sought-after diamond cuts.
Impact on Diamond’s Light Performance: The star facets are key contributors to a diamond’s light performance, including the creation of fire (the dispersion of light into its spectral colours) and brilliance (the return of white light). When cut well, star facets help maximise a diamond’s overall visual impact by ensuring the diamond sparkles intensely.
Role in Diamond Grading:
In diamond grading, star facets are evaluated as part of the overall cut quality. The precision of the cut and the symmetry of the facets contribute to the diamond’s grade in terms of how well it reflects light and sparkles. Well-executed star facets will help improve the overall cut grade of the diamond, as they are directly involved in achieving the maximum brilliance.
Star facets are an essential part of the round brilliant cut diamond, contributing to its signature brilliance, fire, and sparkle. Positioned around the table facet, these triangle-shaped facets create the appearance of a star and help to reflect light in all directions, making the diamond sparkle with incredible intensity. Their precision and symmetry are crucial to achieving the diamond’s full potential, and they play a major role in the overall beauty of a well-cut diamond.