Rare, enduring and a part of the earth’s history; yes, there are many reasons that we love diamonds, but it is perhaps the sparkle that remains the most important factor of all. The sparkle of a diamond is entirely unique. Even those gemstones which exhibit similar qualities, such as moissanite, cannot match the exact light play of a diamond.
So why do diamonds sparkle? And how can you find the most sparkly diamond possible?
Cut is King
Rough diamonds contain the potential for fantastic sparkle, but it must be unleashed by a skilled cutter. Using complex equations that have been formulated over the centuries, the best cutters will assess the natural rough, a cut according to the best results, not the maximum carat yield.
They will also cut to remove areas that are heavily included where possible. The majority of diamonds contain inclusions in varying degrees. Flawless diamonds are extremely rare. Large inclusions, or those positioned directly in the table of the diamond can inhibit light return and reduce sparkle.
A heavily included diamond will look dirty and lacklustre. Aim for eye clean diamonds between an SI1 – VS1 for the best beauty/budget balance.
What is diamond fire?
Diamond fire describes the flashes of rainbow colored light we see in diamonds. It is caused by the diamond’s facets acting like a prism and refracting the white light into the spectrum of colored light.
A little fire creates vibrant and fleeting bursts of color, however too much can create a ‘disco ball’ effect. Moissanite has a higher refractive index than diamond which is why they display an abundance of colored light, but lack in scintillation and brilliance.
What is Scintillation?
Scintillation is the ‘blinking’ or twinkling effect that we see in diamonds. It is created by a balance of light and the absence of light. For example, a chessboard looks more distinctive and eye catching that a plain white sheet of paper. Scintillation gives ‘movement’ to the diamond, creating the sparkling effect.
Without the areas of dark, a diamond would just be a bright to look at without balance, a bit like light reflecting off a mirror.
What is Brilliance?
Brilliance describes the white light that is reflected by a diamond back into the viewer’s eye. Brilliance is often considered the foundation of sparkle; without it, diamonds would look flat. This is where diamond color also come into play – bright, colorless diamonds are the most sought after. Any distinctive color in the body of a diamond will cause a yellow, grey or brown tinge which also dulls the sparkle.
For the best-looking diamonds, look for those which carry a GIA diamond report (this Washington DC jewelry store has a great collection).
A reliable diamond report will contain accurate and consistent grades pertaining to clarity, cut proportions and symmetry all of which contribute for the ‘sparkle factor’ of diamond.
Take advantage of online vendors who provide GIA diamond reports with their large collections of loose diamonds. They often have filter tools which allow you to quickly refine your choices based on shape, cut, color, clarity and carat weight.