Diamonds come from nature and most of them come with diamond fluorescence. Loose diamonds that are submitted to the GIA (Gemological Institute of America) are going to be graded on the level of diamond fluorescence. Until now the GIA has graded overtime 25 to 35 percent diamonds that exhibit some fluorescence. However, only 10% of those diamonds show that strong level of a fluorescence that it gets on the diamond certificate.
But what is the impact if that diamond you liked has a note of diamond fluorescence?
This post describes:
- What is Diamond Fluorescence
- What fluorescence strengths notes give GIA
- What is the Impact of Diamond Fluorescence on price and appearance
● What is Diamond Fluorescence?
Diamond fluorescence means in the simplest way the effect that ultraviolet (UV) light (black light) has on a loose diamond. Thus, the visible light that a diamond emits when it is exposed to the UV rays.
The GIA refers fluorescence to the intensity of the long wave UV that is an essential part of daylight.
● What fluorescence strengths notes gives GIA?
• Very strong
• Extremely strong (but very rare)
Photo credit: GIA: Gemological Institute Of America
● What is the Impact of Diamond Fluorescence?
According to the GIA, the overwhelming majority of the loose diamonds have a level of fluorescence that has no noticeable effect on the appearance. In addition, an average person will not see the difference between a diamond with a fluorescence rating and diamond without fluorescence rating.
An example is that in a study people like diamonds with medium to strong fluorescence better. However, diamonds with extremely strong fluorescence appear hazy or oily… extreme fluorescence is rare as only 0.2% of the GIA diamonds is graded this level.
However, diamond fluorescence sightly affects diamond prices.
DIAMOND FLUORESCENCE IMPACT ON PRICE CHANGE in %
|COLOR||CARITY||FAINT Fl.||MEDIUM Fl.||STRONG Fl .||V. STRONG Fl.|
|D – F Grade||IF – VVS2||up to -1%||min -3 to -7%||min -7 to -10%||up to -15%|
|VS1 – VS2||NO CHANGE||min -1 to -2%||min -3 to -5%||up to -10%|
|SI1 – I3||NO CHANGE||NO CHANGE||up to -1%||up to -3%|
|G – H Grade||IF – VVS2||up to -1%||min -1 to -3%||min -3 to -5%||min -7 to -10%|
|VS1 – VS2||NO CHANGE||up to -2%||min -2 to -3%||up to -10%|
|SI1 – I3||NO CHANGE||NO CHANGE||NO CHANGE||NO CHANGE|
|I – M Grade||IF – I3||NO CHANGE||up to -2%||up to -2%||up to -2%|
Besides that, the strength of the fluorescence does not influence the integrity of the diamond. But as the fluorescent glow is usually blue the fluorescence can upgrade diamonds of I-M color by appearing whiter. That is why we see in the industry that I-M diamonds sell better with a medium to very strong fluorescence.
Extreme fluorescence does impact the diamond appearance by being oily or hazy. I-M diamonds benefit from some fluorescence to appear whiter.
Bottom line, Faint Blue Fluorescent diamonds improve the appearance of color in the diamond as they never appear hazy. Same for Medium Blue Fluorescent diamonds, they will barely show no sign of haziness. Just be careful when you choose a very high color like G in the Medium Blue Fluorescence Range, this could be the worst case scenario.
Better ask advice to our diamond expert as it is very difficult to know how the diamond look like in natural light when you buy online.